The role of K121Q ENPP1 polymorphism in diabetes mellitus and its complications

The aim of the present study was to analyze the frequency of K121Q polymorphism in the ENPP1 gene of Brazilian subjects according to ethnic origin and to determine its possible association with diabetes mellitus (DM) and/or diabetic complications. A cross-sectional study was conducted on 1027 type 2 DM patients and 240 anonymous blood donors (BD). Ethnicity was classified based on self-report of European and African descent. The Q allele frequency was increased in African descendant type 2 DM patients (KK = 25.9 percent, KQ = 48.2 percent, and QQ = 25.9 percent) and BD (KK = 22.0 percent, KQ = 53.8 percent, and QQ = 24.2 percent) compared to European descendant type 2 DM patients (KK = 62.7 percent, KQ = 33.3 percent, and QQ = 4.1 percent) and BD (KK = 61.0 percent, KQ = 35.6 percent, and QQ = 3.4 percent). However, there was no difference in genotype distribution or Q allele frequency between diabetic and non-diabetic subjects (European descendants: DM = 0.21 vs BD = 0.21, P = 0.966, and African descendants: DM = 0.50 vs BD = 0.51, P = 0.899). In addition, there were no differences in clinical, laboratory or insulin resistance indices among the three genotypes. The prevalence of DM complications was also similar. In conclusion, K121Q polymorphism is more common among Afro-Brazilian descendants regardless of glycemic status or insulin sensitivity indices. Likewise, insulin sensitivity and DM chronic complications appear not to be related to the polymorphism in this sample.

Risk factors for decreased bone density in premenopausal women

Osteoporosis is a major health problem. Little is known about the risk factors in premenopause. Sixty 40-50 year old patients with regular menses were studied cross-sectionally. None of the patients were on drugs known to interfere with bone mass. Patients answered a dietary inquiry and had their bone mineral density (BMD) measured. The Z scores were used for the comparisons. A blood sample was taken for the determination of FSH, SHBG, estradiol, testosterone, calcium and alkaline phosphatase. Calcium and creatinine were measured in 24-h urine. A Z score less than -1 was observed for the lumbar spine of 14 patients (23.3 percent), and for the femur of 24 patients (40 percent). Patients with a Z score less than -1 for the lumbar spine were older than patients with a Z score ò-1 (45.7 vs 43.8 years) and presented higher values of alkaline phosphatase (71.1 + 18.2 vs 57.1 + 14.3 IU/I). Multiple regression analysis showed that a lower lumbar spine BMD was associated with higher values of alkaline phosphatase, lower calcium ingestion, a smaller body mass index (BMI), less frequent exercising, and older age. The patients with a Z score less than -1 for the femur were shorter than patients with a Z score ò-1 (158.2 vs 161.3 cm). Multiple regression analysis showed that a lower femoral BMD was associated with lower BMI, higher alkaline phosphatase and caffeine intake, and less frequent exercising. A lower than expected BMD was observed in a significant proportion of premenopausal women and was associated with lower calcium intake, relatively lower physical activity and lower BMI. We conclude that the classical risk factors for osteoporosis may be present before ovarian failure, and their effect may be partly independent of estrogen levels.

Risk factors for development of proteinuria by type II (non-insulin dependent) diabetic patients

1. Renal involvement in non-insulin dependent diabetes mellitus patients is the single most important cause of renal failure. The aim of this study was to evaluate the clinical features and to assess the risk factors for the development of proteinuria by non-insulin dependent diabetic patients. 2. Risk factors (expressed as an odds ratio) were calculated by multiple logistic regression analysis taking into account age, sex, body mass index, known duration of diabetes, presence of arterial hypertension, fasting plasma glucose, cholesterol and triglycerides as independent variables and proteinuria as the dependent variable. Sixty-four normoalbuminuric (24-h albumin excretion rate < 30 micrograms/min, 27 females, mean age 53.7 years) and 53 proteinuric (24-h proteinuria > 0.5 g, 31 females, mean age 59.3 years) were studied. 3. Proteinuric patients were older, with a longer mean known duration of diabetes (12.4 vs 5.6 years), higher mean fasting plasma glucose (214 vs 168 mg/dl) and plasma creatinine (1.5 vs 1.1 mg/dl) and more frequently presented diabetic retinopathy (94 per cent vs 23 per cent ), peripheral neuropathy (94 per cent vs 23 per cent ) and arterial hypertension (73 per cent vs 16 per cent ) than normoalbuminuric patients. Age > 50 years, body mass index > 28.6 kg/m2, known duration of diabetes > 10 years, presence of arterial hypertension, and fasting plasma glucose > 160 mg/dl were significantly and independently associated with development of proteinuria

Effect of age and sex on glomerular filtration rate measured by 51Cr-EDTA

The effect of age and sex on glomerular filtration rate (GFR) was measured by the 51 Cr-EDTA radioisotopic method in 76 normal individuals (43 women and 33 men). Age has a significant effect on GFR. Subjects aged 41 to years have GFR values [104,5 ñ 16.5 ml min-1 (1.73 m2)-1, N=43] lower than younger individuals aged 20 to 40 years [116.6 ñ 11.2 ml min-1 (1.73 m2)-1, N=33]. GFR decreases after 40 years of age by approximately 6.0 ml min-1 (1.73 m2)-1 per decade. GFR values in women [105.9 ñ 16.0 ml min-1 (1.73 m2)-1, N=43] were lower when compared to men [114.8 ñ 14.3 ml min-1 (1.73 m2)-1, N=33]. We conclude that the effect of sex and age must be taken into account when establishing reference values for GFR