Foot Ulceration and Lower Limb Amputation in Type 2 Diabetic Patients in Dutch Primary Health Care

ILONA STATIUS MULLER 1 WIM J.C. DE GRAUW PHD 0 WILLEM H.E.M. VAN GERWEN 0 MARIE LOUISE BARTELINK PHD 1 HENK J.M. VAN DEN HOOGEN 0 GUY E.H.M. RUTTEN PHD 1 0 Department of Family Medicine of the University of Nijmegen, Academic Research Network, Nijmegen, the Netherlands. and Patient Oriented Research, University Medical Centre Utrecht , P.O. Box 85060, 3508 AB Utrecht , the Netherlands 1 Julius Centre for General Practice and Patient Oriented Research, University Medical Centre Utrecht , Utrecht, the Netherlands; and the OBJECTIVE - To determine the incidence of foot ulceration and lower limb amputation in type 2 diabetic patients in primary health care. RESEARCH DESIGN AND METHODS - Data on type 2 diabetes were collected by the Nijmegen Monitoring Project between 1993 and 1998 as part of a study of chronic diseases. The records of all patients recorded as having diabetic foot problems and those who died, moved to a nursing home, or were under specialist care were included. The annual incidence of foot ulceration was defined as the number of type 2 diabetic patients per patient-year who developed a new foot ulcer. Incidence of lower limb amputation was similarly defined. Additional information was collected on treatment of foot ulcers. RESULTS - The study population of type 2 diabetic patients increased from 511 patientyears in 1993 to 665 in 1998. The annual incidence of foot ulceration varied between 1.2 and 3.0% (mean 2.1) per year; 25% of the patients had recurrent episodes. The annual incidence of lower limb amputation varied between 0.5 and 0.8% (mean 0.6). Ten of the 15 amputees died, and 12 of 52 (23%) patients with ulceration had a subsequent amputation or a previous history of amputation. In 35 of the 73 (48%) episodes of ulceration, only the family physician provided treatment. Patients with foot problems were older and had more cardiovascular disease, retinopathy, and absent peripheral pulses. CONCLUSIONS - The incidence of foot ulceration and lower limb amputation in type 2 diabetes is low; nevertheless, recurrence rates of ulceration and risk of amputation are high, with high mortality. - I with type 2 diabetes has shifted from n the Netherlands, the care for patients outpatient clinics to primary health care. Approximately three-quarters of all type 2 diabetic patients are treated by family physicians. The family physician acts as the gatekeeper for hospital-based care. The frequency of diagnosis of type 2 diabetes is rising (1). It is estimated that by the year 2010, there will be 400,000 500,000 diabetic patients in the Netherlands (2). The family physician plays a central role in the treatment of the diabetes-related complications, such as the diabetic foot, and decides on referrals to hospital clinics (3). Studies outside the Netherlands report varying prevalences in type 2 diabetic patients of foot ulceration (27%) and of lower limb amputation (0.2 4%) in primary health care (4 9). A 14-year incidence of lower limb amputation of 9.9% is reported in primary care (10). Dutch studies report that the prevalence of ulceration is 1.8% (11,12). Nothing is known about its incidence. The ageadjusted incidence of amputation in the Netherlands is estimated to be 35.1 per 10,000 diabetic males and 17.4 per 10,000 diabetic females (13). In primary health care in the Netherlands, it is estimated that 13% of diabetic patients are at risk for developing foot problems (11). The most important intervention to prevent foot ulceration and its consequences is early recognition of high-risk patients and referral to appropriate multidisciplinary teams (14 17). High risk can be detected from the history of a previous ulcer/amputation and clinical examination; for example, impaired monofilament sensation and vibration perception, absent Achilles tendon reflex, callus foot deformities, inappropriate footwear, and absent pedal pulse (3,14,18). The International Working Group on the Diabetic Foot advises an annual foot examination for all diabetic patients and more frequent examinations for those at high risk (3). Since 1989, the Dutch College of General Practitioners has recommended an annual foot inspection (19), but review of patients records showed that this recommendation has been the least honored by family physicians, who feel they have no time to comply with it (20). The revised recommendation advises education on foot care and inspection annually for all diabetic patients and every 3 months for those who have had previous ulceration or have foot deformities or neuropathy. Referral is recommended when a foot ulceration has not healed within 2 weeks or the ulcer is deep. A classification of foot ulceration is not obliged (21). Despite these recommendations, little is known about the extent of the diabetic foot problem and its management in Dutch family practice. We therefore studied the diabetic cohort of the Academic Research Network of the Department of Family Medicine, University Nijmegen, the Nijmegen Monitoring Project (NMP). The NMP is an ongoing prospective longitudinal study of the course of a number of chronic diseases in 10 family practices, run by 26 family physicians, with a total population of 45,500 patients (22 24). Primarily, we sought to determine the incidence of foot ulceration and lower limb amputation in type 2 diabetic patients and, secondarily, to study the referral rate of patients with foot ulceration. RESEARCH DESIGN AND METHODS The NMP In the NMP, the family physicians register includes, among others, all their diabetic patients, including those under specialist care. Patients are included under a standard protocol if the diagnostic evidence agrees with the World Health Organization criteria (1985) on diabetes (22,23,25). Patients who were treated with insulin within 1 year after diagnosis and remained on it were considered to have type 1 diabetes and were excluded. In the NMP, a limited monitoring is carried out every 3 months, and a full evaluation is made annually. As part of this annual review, foot examination was performed. This implies that the condition of the feet was recorded annually and graded as follows: 1) no abnormalities; 2) abnormalities and/or mycosis of the nails; 3) pressure marks and/or ulceration; 4) combination of 2 and 3; 5) amputation below the ankle; and 6) amputation at higher level. No distinction was made between pressure mark and foot ulceration, no prior grading of foot ulceration was determined, and no parameters were defined to distinguish between the different types of ulcers. Defining neuropathy was restricted to monitoring the presence or absence of the Achilles tendon reflex. No data on sensory neuropathy was collected. As a parameter for peripheral vascular disease, absence or presence of peripheral foot pulses was determined. Prevention of foot ulceration consisted of annual investigation of the feet and education. The family physicians did (...truncated)