NEPHROPATHY IN LOW-INCOME DIABETICS - THE MEXICO-CITY DIABETES STUDY

Among the most serious complications associated with diabetes mellitus (DM) is nephropathy (DN). In Mexico, there is little information on t he frequency and clinical characteristics of DN in the Mexican populat ion,We present results of a population-based survey designed to estima te the prevalence of DN. The low income population consisted of 15,532 inhabitants. All 35- to 64-year-old males and nonpregnant women resid ing in the survey area were identified as eligible for the study (3505 ; 22.6%). A home interview was obtained ill 2810 (80.2%). A physical e xam with oral glucose tolerance test was obtained in 2282 (81.2% of th ose interviewed). DM was diagnosed in 304 (crude rate 13.3%). Mean age for men and women with DM was 51.6 +/- 8.4 and 52.2 +/- 7.5, respecti vely. Duration of DM in men was 9.2 +/- 8.1 and in women, 7.3 +/- 6.7 years. Hypertension was diagnosed in 19.8% of men and 18.1% of women. Diabetic retinopathy of any level was found in 55.4% of men and 45.7% of women. Mean glycohemoglobin in men was 9.6 +/- 2.1 and in women 9.5 +/- 2.2% (normal 4 - 8%). At baseline, proteinuria (1+ or more, by di pstick) was found in 24.7% of men and 9.6% of women, microalbuminuria (MA) in 84.4% of men and 63.8% of women. Quantitative albuminuria was abnormally high in 54.7% of men and 40.3% of women. In the 203 diabeti cs studied with 24 h urine collection for creatinine clearance, normal renal function was found in 69.1% of men acid 47.5% of women, reduced renal function was found in 26% of men and 50% of women, renal insuff iciency was diagnosed in 4.9% of men and 1.6% of women. One patient wa s on dialysis and in a subsequent follow up, we found that 2.3% of the patients had died of renal failure, six men (46 - 63 years) and a wom an of 62 years. We conclude that DN is a very serious threat to this p opulation. The high case fatality rate associated with this condition maintains a low prevalence. It is important to develop a program to di minish the frequency of this condition.