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Abstract
Introduction Evidence on the prevalence of foot problems among people with diabetes in India at a national level is lacking. Hence, this study was aimed to assess the burden of high-risk (HR) feet in people with diabetes across India.
Research design and methods A cross-sectional national-level project ‘Save the Feet and Keep Walking’ campaign was conducted by the Research Society for the Study of Diabetes in India (RSSDI) from July 10, 2022 to August 10, 2022. A modified version of 3 min foot examination was used to assess the foot problems. Around 10 000 doctors with RSSDI membership were trained online to conduct foot screening and provided a standardised monofilament for detection of loss of protective sensation. People with diabetes aged >18 years who visited the clinics during the study period were examined for foot problems. Data were collected online using the semi-structured questionnaire. A total of 33 259 participants with complete information were included for the final analysis. The foot at risk was categorised based on International Working Group on the Diabetic Foot guidelines 2023.
Results Nearly 75% of the participants were aged above 45 years. Around 49% had diabetes duration >5 years and uncontrolled diabetes (hemoglobin A1c >8%). Presence of history of foot ulcer (20%), lower limb amputation (15.3%), foot deformities (24.5%) and absence of diminished dorsal pedis and posterior tibial pulses (26.4%) was noted in the study participants. Around 25.2% of them had HR feet and highly prevalent among males. Diabetic kidney and retinal complications were present in 70% and 75.5% of people with HR feet. Presence of heel fissures (OR (95% CI) 4.6 (4.2 to 5.1)) and callus or corns (OR (95% CI) 3.6 (3.3 to 4.0)) were significantly associated with HR feet.
Conclusions One-fourth of people with diabetes were found to have HR feet in India. The findings are suggestive of regular screening of people with diabetes for foot problems and strengthening of primary healthcare.
- diabetic foot
- risk assessment
- foot deformities
- India
Data availability statement
Data are available on reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information. Not applicable.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
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WHAT IS ALREADY KNOWN ON THIS TOPIC
The evidence on burden of diabetic foot problems is available at a clinic level or a community level with smaller sample size and not at a national level.
WHAT THIS STUDY ADDS
This study gave a broader insight into the burden of foot problems in a large sample of people with diabetes.
This also showed the feasibility and application of a uniform and a simple 3 min foot examination tool across many clinics in India.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
The national-level Non-Communicable Diseases (NCDs) program is focused on prevention and treatment of diabetes.
This study finding throws the light on the burden of diabetic foot problems at national level.
Hence, it would emphasize appropriate planning and strengthening the primary healthcare to focus on primary prevention of diabetic foot complications.
Introduction
India has second highest number of people living with diabetes (101.3 million) in the world next to China (140.9 million).1 2 Diabetic foot-related problems is one of the most common problems in people with diabetes. India also faces the increasing burden of foot-related problems among people with diabetes.3–7 The recent report on the diabetes-related foot complications by the International Diabetes Federation (IDF) suggests that there is a large amount of information available on diabetic peripheral neuropathy (DPN) worldwide compared with peripheral arterial disease (PAD). The same report suggests that PAD estimates were found only for several African countries, South Korea and Australia. It also showed there were less diabetes-related foot complications in the IDF South East Asian (SEA) region compared with other regions mainly North Africa and the South and the Central American Region.8 The paucity of larger surveillance or registry and prospective data on the burden of diabetes-related foot problems in the SEA or any other IDF region itself may pose an important challenge for understanding the intraregional burden of diabetes foot-related problems and also to make an inter-region comparison worldwide. Hence, there is a need for country/nationwide data on the diabetic foot problems in India and other countries in this region.
The hospitalisation costs was significantly higher in people with diabetic foot complications compared with people with other diabetic complications9 10 and increasing costs for diabetic foot disease has been observed in numerous health economies.11 12 Many studies have revealed that low level of literacy, awareness about foot care practices and sociocultural factors such as barefoot walking remain the main reasons for the onset of foot-related problems among people with diabetes in India.13–15
Hence, timely screening and referral mechanism to appropriate healthcare facilities is mandatory for people with diabetes to prevent diabetes-related foot complications. Estimates of diabetic foot disease are equally important for planning treatment strategies and developing referral mechanisms, which are crucial aspects of the health system. Hence, identifying feet at high risk of foot ulcer or amputation—specifically, detecting the feet with loss of protective sensation (LOPS)—is very important for limb salvage in people with diabetes. India being the highest contributor of diabetes burden to the SEA region should be focused on the screening for the people at risk of developing diabetes-related foot complications.
Hence, the diabetic foot task force of the largest diabetes research network RSSDI conducted this larger cross-sectional survey at Pan India level to determine the prevalence of high-risk (HR) feet with LOPS among people with diabetes. This survey also aimed to study the distribution and pattern of LOPS and PAD among people with type 2 diabetes. The study also aimed to identify the risk factors associated with the presence of HR feet.
Methods
Study design and setting
This was a larger cross-sectional multicentric study conducted across Pan India. The diabetic foot screening camps were conducted across the states of India covering 10 000 clinics, where people with diabetes made their outpatient (OP) visit from July 10, 2022 to August 10, 2022. The camps were conducted all over Indian states, including clinics where diabetologists and/or general practitioners were available. Majority (84.1%) of the clinics were located in urban or semi-urban areas and 15.9% were located in rural areas (village or small town). The foot screening was conducted as part of ‘Save the Feet and Keep Walking Campaign’ by the National RSSDI.
Study criteria and participants
The screening included people who visited the diabetes clinic for their treatment and aged above 18 years. Both male and female participants were included. People with severe illness and ulcers for whom the monofilament testing cannot be performed were excluded from the screening.
Study procedure and investigations
A screening tool was prepared modifying the 3 min foot examination procedure16 and shared with the doctors at the respective clinics. This tool includes 1 min each for (1) medical history of the person with diabetes, (2) physical examination of the feet and (3) foot care education. Participant details such as age, gender, duration of diabetes, smoking habit, fasting blood sugar (FBS), random blood sugar (RBS) and postprandial blood sugar (PPBS) levels, as well as hemoglobin A1c (HbA1c) (if done within 3 months from study period), were collected. History of end-stage renal disease (on dialysis/renal transplant/estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2) and diabetic retinopathy (visual impairment) were noted from their medical records. The details on history of diabetic foot ulcer (DFU), related revascularization/angioplasty and amputation were also recorded. The data were entered using an online survey form at each clinic by the trained investigator.
Foot examination also includes dermatological exam, neurological exam and musculoskeletal exam.16 The data collection form can be found in online supplemental form 1. Several online training programs were conducted for the RSSDI members. A video demonstrating foot examination (online supplemental video 1) and a standardised monofilament for detection of LOPS were also provided to the doctors. A total of 20 monofilaments (Medical Monofilaments 5.07/10 g—item code: MF10GM, Diabetik Foot Care India) made of nylon fibre were given to each participating clinic. Instructions were also shared on the RSSDI ‘Save the Feet and Keep Walking’ online portal that ‘monofilaments tend to loose buckling force temporarily after being used several times on the same day or permanently after long duration’. Hence, it was suggested not to use the same monofilament after it was used for assessing 10–15 participants the same day and were asked to change the monofilament permanently after every 50–70 participants. It was also validated for its accuracy in alignment with vibration perception threshold(VPT) by biothesiometry among 198 participants in one of the diabetes specialty centres that took part in this study. Monofilament had yielded sensitivity and specificity of 94.6% and 77.0%, respectively. The accuracy was 86.8%, with a positive predictive value of 84% and negative predictive value of 91.8%.
Supplemental material
Supplementary video
The participants were asked to lie in a supine position on a testing table and close their eyes before doing this test. The sensation of the pressure using 10 g monofilament on a proximal site (eg, upper arm) was also demonstrated to the participant. The device was placed perpendicular to the skin at the foot sites, with the pressure applied until the monofilament buckles. It was held for 1 s and released. The participants were asked to respond ‘yes’ or ‘no’ if they perceived the pressure and also to identify the correct site when the monofilament was applied to a particular site.17
The foot risk was classified as very low or no risk (no LOPS and no PAD), low risk (LOPS or PAD), moderate risk (LOPS and PAD or LOPS and deformities or PAD and deformities) and high risk (LOPS or PAD and one or more of the other risk factors such as history of DFU or lower extremity amputation or end-stage renal disease) based on International Working Group on the Diabetic Foot (IWGDF) guidelines 2023.18
Statistical analysis
Descriptive statistics were reported. Median (range) and percentages were reported for continuous and categorical variables, respectively. Median and χ2 tests with pairwise comparison were performed to see the statistical significance between the study groups (very low-risk, low-risk, moderate-risk and HR feet). A multivariable regression was performed to identify the factors associated with the feet at risk. Feet at risk was taken as the dependent variable and age, gender, duration of diabetes, smoking habit, presence of callus or corns, presence of open wound/heel fissures as independent variables. The OR with 95% CI and p value were reported. A p value of <0.05 was considered statistically significant. Data analysis was performed using SPSS V.29.0.
Results
A total of 33 506 eligible individuals with diabetes took part in the screening across the clinics. A total of 33 259 participants were included in the final analysis after excluding the participants with incomplete information.
The sociodemographic and diabetes profile of the study participants (n=33 259) is provided in online supplemental table 1. It was observed that about 30% of the participants were in the age group of 46–55 years. Majority (68.7%) of them were male participants. Around 49% of the participants had diabetes duration of >5 years. Nearly 51% had uncontrolled blood sugar (HbA1c >8.0%). Around 13% had smoking habit. The participants with history of foot ulcer were 20%, while 15% were found to have history of lower limb amputation.
Supplemental material
The prevalence of signs and symptoms of diabetic foot risk and musculoskeletal profile of the study participants is given in table 1. Majority (45%) had experienced the symptoms of burning or tingling sensation in their feet followed by loss of lower extremity sensation (32.8%) and leg or foot pain (31.3%). Around 24.5% were found to have deformities and dorsal pedis and posterior tibial pulses were not palpable in 26.4%.
Prevalence of signs and symptoms of diabetic foot risk and musculoskeletal profile of the study participants
The discolored or ingrown or elongated nails were present in 14% of the study participants. Around 13% had discolored/hypertrophic skin lesions, calluses or corns and 12% had heel fissures. The sensation to 10 g monofilament was not perceived among 24% of the study participants (table 2).
Dermatological and neurological profile of the study participants
About 25% of the participants had high level of diabetes foot risk, while 2.5% and 5% had moderate and low levels of diabetes foot risk, respectively (figure 1A). Male participants had significantly high level diabetic foot risk compared with female participants (26.1 vs 23.1; p<0.0001) (figure 1B).
(A) Level of diabetic foot risk in the study population. (B) Level of diabetic foot risk by gender.
The participants in the moderate and high levels of diabetes foot risk were 3–4 years older than those in the low and very low foot risk groups (p<0.001). The median FBS levels were found to be significantly different from very low-risk (139 mg/dL), low-risk (145 mg/dL), moderate-risk (156 mg/dL) and HR groups (150 mg/dL); p<0.001. However, they were found to be high in the moderate-risk group compared with the very low-risk, low-risk and HR groups. Similarly, there was a significant increase of PPBS levels noted from very low-risk to moderate-risk groups (210, 213, 230 mg/dL; p<0.001), with a slight dip in HR group (217 mg/dL). Median HbA1c% (8.3% vs 8.0% and 8.1%; p<0.001) was higher in HR group compared with other groups. It was noted that 70% of people with HR feet were found to have diabetic nephropathy, while none was present in other groups. The proportion of retinal complications increased significantly from very low-risk to HR group (8.7%; 11.3%; 24.3% and 75.5%, p<0.001) and the difference was statistically significant (table 3).
Age, biochemical profile and microvascular complications of the participants based on diabetic foot risk classification
Table 4 shows the factors associated with the HR feet. The presence of heel fissures emerged as a strong independent risk factor significantly associated with HR feet having the odds of 4.6 (95% CI 4.2 to 5.1) (p<0.001), followed by the presence of callus or corns (OR 3.6 (95% CI 3.3 to 4.0), p<0.001). The participants who were smokers were 2.3 times more likely to have HR feet compared with non-smokers. Similarly, participants aged >65 years were 2.3 times more likely to have HR feet compared with those aged ≤45 years. Increasing HbA1c% was also found to be associated with HR feet, with an OR of 1.2 (95% CI 1.1 to 1.3, p<0.001).
Factors associated with high-risk feet: a multivariable logistic regression
Discussion
To our knowledge, this is the first ever large national-level study conducted in India to assess the prevalence of HR feet among people with diabetes. Paucity of comprehensive data and methodological variations across the studies led us to conduct this study.
Our findings revealed that three-fourths of the study participants were aged >45 years and the median age of the participants who had HR feet was 56 years. Similarly, other Indian studies also showed that more than half of their study participants were aged >50 years and median age was >55 years.4 19 20 Male participation was higher than females, while similar gender distribution was observed in an earlier study conducted in 201021 and in contrast, other studies showed more female participation.4 19 22 ,23Nearly half of the participants were found to have diabetes for >5 years in our study and this finding was consistent with other studies.19 20 23
In this study, around one-fifth of them had history of foot ulcers and about one-fourth of the participants had HR feet. Existing evidence suggests a stronger relationship between recurrence of foot ulcer in those with history of foot ulcer24 and a review of studies had estimated 19%–34% of people with diabetes had risk of developing foot ulcer in their lifetime.25 A population-based cohort which analyzed data of 225 787 persons with newly diagnosed diabetes found 34% were at low, 7% at moderate and 1% at high risk of diabetic foot based on the National Institute for Health and Care Excellence (NICE) guidelines. This cohort showed 48.2% of people who had HR feet were white population and 0.1%–0.8% belonged to Carribean/black/African/Asian/Asian British population or other ethnic groups and ethnicity was missing in about 50.1%.26 While an observational study conducted among 10 421 people with diabetes in the UK reported 8% of moderate risk and <1% of HR feet at baseline based on NICE guidelines and after 2 years it found 5.1% who were at low risk had progressed to moderate risk.22
A larger prospective cohort study conducted in Pakistan, involving 18 119 participants, reported that 21% of them were classified as being at high risk of foot ulceration.27 The participants classified as having HR feet in our study were determined based on the IWGDF guidelines, which include presence of LOPS and PAD, and one or more additional factors like the presence of ulcer or amputation, or the presence of renal complications. This contrasts with the classification in this cohort, which used the Neuropathy Disability Score with a score >6. Another study conducted in India showed 67% of feet were classified as at risk based on the presence of one or more factors, including diabetic neuropathy, peripheral vascular disease (PVD), foot deformity, history of foot ulceration, presence of other microvascular complications, elderly patients (aged ≥65 years) and patients living alone.28 Additionally, this study reported that 35% of these at-risk feet participants had neuropathy and 12.6% had PVD. A multicentric cross-sectional study conducted in 16 centres in Bangladesh,29 covering 1200 people, found that 28.5% of the participants had HR feet, while 11.6% had moderate-risk feet based on the IWGDF guidelines.
In our study, a history of amputation was found in 15% of the participants, whereas a multicentric study conducted in Bangladesh reported amputation in only 8% of the participants.29 Several studies including meta-analysis showed that people with history of amputation have increased risk (3–11 times) of foot amputation.
Other important risk factors such as history of foot ulcer, smoking habit, male gender and presence of PAD were also found to have a strong association with recurrence of foot ulcer and amputation.30–33 In our study, 12.6% of the participants had smoking habit and they were also found to have 2.3 times higher odds of having feet at risk compared with those without a smoking habit. Smoking contributes to the occurrence of PAD/PVD. The presence of PAD is one of the main risk factors for DFUs and it has been independently associated with poor ulcer healing and an increased risk of amputation.34–36 In our study, the absence of dorsalis pedis and tibial pulses were found in around 26.4% of the screened participants. A multicentric study conducted a decade ago showed that 35% people who underwent amputation had PVD.21 While a large-scale study conducted in rural Karnataka showed 22.2% of people with diabetes had feeble pedal pulse.20Another study conducted in a rural community showed 33% had PAD with DPN.21 While another study conducted in an urban foot clinic showed that around 87% of the study participants who had vascular symptoms got confirmed with PAD upon further investigations and 62% among them had known history of diabetes .4 The rural-urban variation in the presence of PVD/PAD is very much evident. But it was surprised to note that only 0.3% had PAD in Bangladesh.29
Our study showed that foot deformities were present in 25% of the participants. Other studies reported foot deformities in varying percentages: 9.8%,4 10.2%23 and 34.7%,20 respectively. People with diabetes have high prevalence of foot deformities even in the presence of peripheral neuropathy.37 Therefore, it is crucial for people with diabetes to be regularly assessed for foot deformities. Early intervention can significantly reduce the risk of developing foot ulcers. The burden of skin lesions such as fissures (12.6%), callus or corns (11.6%) was comparable with a study conducted in Indian urban context.4 In contrast, rural studies had shown higher prevalence of fissures (31%–81.9%) and callus (14.5%–43.4%).19 20 23 The presence of fissures (OR 4.6) and callus (OR 3.6) also showed strong association with HR feet in our study.
The present study also showed nearly three-fourth of the participants with HR feet had renal and retinal complications. There is considerable evidence available on the established link between chronic kidney disease and diabetic foot. Studies have shown that end-stage renal disease and chronic conditions are associated with a higher incidence of foot ulcers, prolonged healing time and recurrence of ulcers, and a greater likelihood of lower limb amputation.38–40 Studies have also shown a strong association between diabetic retinopathy and foot ulcers. The rate of retinopathy in people with DFU was found to be 2–4 times higher compared with those without foot ulcers. Chronic foot ulcers were also associated with increased progression of retinopathy.41 42 This link emphasizes the screening for other microvascular complications at regular intervals in people with HR feet.
Considering the high burden of diabetes across the countries and also the paucity of data on diabetes-related foot problems, there is a need for the diabetic foot assessment with a standard and simple tool covering larger populations. This study has demonstrated the feasibility of effectively screening a larger population for foot problems using a simple assessment tool. As the screening mainly involved training costs for investigators in foot examination and the recurring cost for monofilaments, designing this kind of multicentric study may prove to be more cost-effective in low-resource settings.
However, the participants with HR feet were not prospectively followed up to assess the incidence of foot ulcers among them. Hence, it is one of the important limitations of this study. The authors have planned to address this by establishing a registry of people with HR feet and conducting longitudinal follow-ups to evaluate the incidence of foot ulcers. This approach will further benefit in evaluating the effectiveness of this screening.
Limitations of the study
As the doctors were voluntarily taking part in this ‘RSSDI Save the Feet and Keep Walking Campaign’ and conducted the foot screening in their respective clinics, the authors could not categorise and confirm the equal representation of clinics/sample from all the states and also urban or rural areas of the Indian states and hence the results cannot be generalised with respect to rural and urban areas specifically. It will be addressed in the future studies.
Conclusions
One-fourth of the study population had HR feet. India being a low- and middle-income country with one-fourth of its population having diabetes or prediabetes should emphasize more on strengthening the primary care services for diabetes treatment and prevention. This will pave the way for preventing economic burden associated with foot complications. Furthermore, improving primary care services will contribute to enhancing the overall health and well-being of the nation.
Data availability statement
Data are available on reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information. Not applicable.
Ethics statements
Patient consent for publication
Ethics approval
This study was approved by the Ethics Committee of Professor M Viswanathan Diabetes Research Centre (reference IEC/N-001/06/2022). The doctors voluntarily participated in this 'Save the Feet and Keep Walking Campaign' and the foot screening was done as part of their routine examination for the persons with diabetes who made their outpatient visit in the respective clinics during the campaign. Foot examination was done free of cost. An oral consent was taken from the participants to undergo this screening for the identification of high-risk feet and they were informed that these data may be used for further scientific analysis without revealing their identity.
Acknowledgments
We would like to acknowledge Mr Mayank, National RSSDI Secretariat for his support in data collection and USV India for providing the standard monofilament to the RSSDI members who participated in the study. We extend our heartfelt thanks to the study participants for their valuable time and cooperation. We would also extend our gratitude to all the members of the RSSDI Diabetic Foot Task Group and the doctors who participated and conducted foot screening at their respective clinics and provided data online.
References
Supplementary materials
Supplementary Data
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Footnotes
Contributors VV conceived and designed the study and along with AG, SA, BMM, BS, VK and RKS implemented and managed the study. AG and SA involved in the data acquisition. AD, SK and SS involved in data analysis and interpretation. AD and SK drafted the manuscript. All the authors reviewed and finalized the manuscript and agreed to authorship. VV is the author responsible for the overall content as the guarantor.
Funding We did not receive any external funding
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.