Reduction in body weight helps to delay the onset of diabetes even in non-obese with strong family history of the disease

Of the 1200 non-diabetic offspring of non-insulin-dependent diabetic patients registered under the prevention programme, 262 (M:F 189:73) were available for analysis with greater than or equal to 4 years of follow-up. All of them had been prescribed a calorie restricted diet to suit their body weight, occupation and age, and were advised to restrict the use of refined carbohydrates and fats. Regular exercise was also advised. Compliance with these prescriptions was assessed at each follow up. At the time of analysis, it was noted that only 14.5% had developed diabetes in a period of 8 +/- 4.2 years even though many of them had impaired glucose tolerance at entry in the programme. Multiple regression analysis showed that initial 2 h plasma glucose, initial glucose tolerance and gain in body weight were strong predictors of diabetes. Weight loss occurred in persons who adhered to diet and exercise programmes and conversion to diabetes was lower in them compared to those who gained weight (P < 0.002). Although the rate and degree of obesity is less among Indians, it has been observed in several earlier studies that even a minor increase in body mass index increased the risk of diabetes. This study highlights the fact that measures to control weight helps to delay the onset of diabetes even in the non-obese despite a strong family history of the disorder.

Rising prevalence of NIDDM in an urban population in India

A survey conducted in 1988-1989, in the city of Madras, South India, showed that the prevalence of diabetes mellitus in adults was 8.2% and prevalence of impaired glucose tolerance (IGT) was 8.7%. The present survey was another cross-sectional study conducted 5 years later in the same urban area to study the temporal changes in the prevalence of diabetes and IGT. The two sample populations surveyed were similar in age structure and socioeconomic factors. In the second survey in 1994-1995, a total of 2,183 subjects, 1,081 men and 1,102 women, with a mean age of 40 +/- 12 years were tested by an oral glucose tolerance test; fasting and 2-h post-glucose plasma glucose were measured. Anthropometric measurements, details of physical activity and clinical history of diabetes were recorded. Age-standardised prevalence of diabetes had increased to 11.6% from 8.2% in 1989 and IGT was 9.1%, similar to 8.7% in 1989. Multiple regression analysis showed age, waist:hip ratio, body mass index (BMI) and female sex were correlated to diabetes. Family history of diabetes showed interaction with age and BMI. Prevalence of IGT correlated to age, BMI and waist:hip ratio. This study highlights the rising trend in the prevalence of non-insulin-dependent diabetes (NIDDM) in urban Indians. The persistent high prevalence of IGT may also be a predictor of a further increase in NIDDM in the future. No significant differences in the anthropometric data were noted in this compared to the previous study.

An association between type 1 diabetes and the interleukin-1 receptor type 1 gene. The DiMe Study Group. Childhood Diabetes in Finland

The polygenic susceptibility to type 1 diabetes is well established and recent studies have demonstrated linkage of a further locus on chromosome 2q to disease. We have studied a polymorphism of the interleukin-1 receptor type 1 gene (IL1R1) on chromosome 2q in type 1 diabetic and control subjects from Finland, the United Kingdom, South India: three populations in which the risk of disease varies from very high to very low. In the medium-risk U.K. population we find a very strong association of IL1R1 with type 1 diabetes (p = 0.0002) but we find no overall association in either the high-risk Finnish or low-risk South-Indian populations. However, we do find heterogeneity of risk at IL1R1 amongst Finnish diabetic subjects according to the possession of HLA-DR associated susceptibility (p = 0.0001); there is an association with IL1R1 in only those Finnish diabetic subjects who do not possess high-risk HLA-DR4 or DR3 haplotypes (p = 0.006), as recently demonstrated for the insulin gene region in this population. We find no such heterogeneity of risk in either the U.K. or South-Indian populations. This study further demonstrates the genetic heterogeneity of disease susceptibility between and within populations and also supports the hypothesis of an interaction of the IL1R1 locus with genes within the HLA and insulin gene regions in the susceptibility to type 1 diabetes.

Incidence of IDDM in children in urban population in southern India. Madras IDDM Registry Group Madras, South India

This study was carried out to estimate the incidence of childhood insulin dependent diabetes mellitus (IDDM) in an urban southern Indian, population. A registry for IDDM has been set up in the city of Madras. South India. Details of newly diagnosed IDDM children, aged less than 15 years, were analysed retrospectively, for a period of 1991-1994. Primary sources were government and service hospitals, large diabetes clinics and secondary sources were diabetes camp, private diabetologists and endocrinologists. A capture-recapture method was used and the estimate of case in the population (1991 census) was calculated. Incidence (case/100,000) was calculated in the total group and then for boys and girls separately. The incidence for the 4 year period was 10.5/100,000/year (CI 5.0). The corresponding values for boys and girls were 12.6 +/- 11 and 9.6 +/- 4.7 respectively. The peak incidence was between 10 and 12 years. This is the first population based incidence data from India and showed that the incidence of childhood IDDM is not low in urban children.

Evaluation of the importance of maternal history of diabetes and of mitochondrial variation in the development of NIDDM

In 79 South Indian nuclear pedigrees ascertained via probands with NIDDM and both parents living, parental diabetic status was established through previously diagnosed NIDDM (n = 97) or oral glucose tolerance testing (n = 61). There was no significant difference between diabetes prevalence in mothers and fathers (60 vs 53 (76% vs 67%), respectively, p = 0.22). 'Age at diabetes diagnosis' survival curves did differ according to parental gender (p = 0.02) but this may reflect gender differences in health provision rather than pathophysiology. No maternal excess effects of the magnitude evident in previous studies were detected, suggesting either ethnic differences or overestimation of the maternal effect when reported histories of parental diabetes have been used. The tRNA(Leu(UUR) gene region was studied for diabetes-associated variation given the role of mutations in this gene in some pedigrees displaying maternal transmission of NIDDM. None of 142 unrelated South Indian NIDDM subjects displayed the MELAS mutation at nt3243. However, sequencing identified two variants of potential importance: (a) at nt3290 in the tRNA(Leu(UUR) gene, seen in 7/142 diabetic and 1/85 control subjects (p = 0.11), (b) at nt3316 in the ND1 gene (4/142 vs 1/85 subjects, respectively (p = 0.51)). Further studies are needed to determine the relevance of these variants to the development of NIDDM.

Effects of pineal indoles and parachlorophenylalanine on seasonal reproduction in the pigeon

The effect of melatonin, methoxytryptophol (ML), methoxytryptamine (MT) and parachlorophenylalanine (p-CPA) on the mass and histology of the testes and the adrenal and thyroid glands and on serum thyroid hormone levels have been studied in the recrudescent phase of the feral pigeon Columba livia. All the pineal indoles showed a common anti-gonadal effect, resulting in the arrest of spermatogenesis and the degeneration of germ cells. Treatment with melatonin resulted in adreno-cortical enlargement and medullary hypertrophy, whereas ML, MT and p-CPA induced medullary enlargement and hypertrophy without having much influence on the cortex. Treatment with melatonin and ML brought about colloid retention in the thyroid follicles, while MT and p-CPA induced colloid depletion and hypertrophy of the follicular epithelium. From the present study, it can be concluded that both pineal indoles and p-CPA induce testicular regression in the breeding phase but do so by different mechanisms.

Diabetic retinopathy at the time of diagnosis of NIDDM in south Indian subjects

Several studies from the U.K. and the U.S. have shown that retinopathy was present at diagnosis of non-insulin dependent diabetes mellitus (NIDDM) indicating the likelihood of a latent phase of hyperglycaemia for a long period. This study looked for the prevalence of retinopathy at diagnosis of NIDDM in South Indian subjects who have a fairly high prevalence of diabetes and also a high rate of undetected diabetes. One thousand NIDDM subjects with varying duration of diabetes underwent detailed ophthalmoscopic examination for retinopathy. It was noted that the prevalence of retinopathy increased linearly with duration of diabetes. Among the 60 newly diagnosed NIDDM, 4 (6.7%) subjects had background diabetic retinopathy. Using a weighted linear regression analysis with percentage of retinopathy in relation to duration, it was estimated that hyperglycaemia could have been present 4.1 years prior to the diagnosis of NIDDM. Although the prevalence of retinopathy at diagnosis in South Indian NIDDM was lower than the other reported values, in view of the high prevalence of diabetes in Indians, a large number of patients would have the risk of microangiopathy even before diagnosis of diabetes is made.

An association in non-insulin-dependent diabetes mellitus subjects between susceptibility to retinopathy and tumor necrosis factor polymorphism

In IDDM an association between diabetic retinopathy and polymorphic markers of MHC has been described. However, these associations are complicated by a primary association between the MHC and IDDM. Because the pathogenesis of retinopathy is likely to be the same in IDDM and NIDDM, NIDDM subjects with retinopathy would be the ideal population to study for an association with MHC markers. The following South Indian subjects were therefore studied: unselected NIDDM (n = 76), unselected IDDM (n = 99), non-diabetic controls (n = 96), NIDDM subjects with maculopathy (MAC), n = 55, NIDDM subjects with proliferative retinopathy (PR), n = 53, and without retinopathy (LTD), n = 46. DNA was amplified and studied using a microsatellite polymorphism located 3.5 kb upstream of TNF-beta within the MHC class III region on the short arm of chromosome 6. No differences in allelic distribution were observed between the random NIDDM subjects and controls (p = 0.17). Differences in allelic distribution were found between unselected IDDM and controls (P = 0.016) and between the NIDDM subjects with maculopathy and/or proliferative retinopathy and no retinopathy (P = 0.006). This association could be accounted for by those patients with proliferative retinopathy (MAC vs LTD, p = 0.23; MAC vs PR, p = 0.07; and PR vs LTD, p = 0.002).

Familial aggregation of type 2 (non-insulin-dependent) diabetes mellitus in south India; absence of excess maternal transmission

The family histories of 976 South Indian Type 2 diabetic patients were recorded in a questionnaire-based survey to establish whether the excess maternal transmission of Type 2 diabetes reported in low prevalence Europid populations was also evident in this medium prevalence population. In 450 families (46.1%), no parental history of diabetes was reported. In 423 families with one parent diabetic, 222 fathers (52.5%) and 201 (47.5%) mothers were diabetic. In the remaining 103 (10.6%) families, both parents were diabetic. In contrast to previous studies, we found no evidence for substantial maternal excess in the transmission of diabetes (325 diabetic fathers vs 304 mothers; p = 0.4; p = 0.07 when compared using life table methods). The age of diagnosis of diabetes in probands was lower than that of their diabetic parents (p < 0.001): furthermore increasing parental history of diabetes was associated with an earlier diagnosis of diabetes in probands (p < 0.001). These results emphasize the extensive familial aggregation of Type 2 diabetes in this population but fail to replicate the evidence for excess maternal transmission evident in lower prevalence Europid populations, suggesting ethnic differences in the extent of this phenomenon.

Insulin receptor substrate-1 gene mutations in NIDDM; implications for the study of polygenic disease

Variations in the coding regions of the insulin receptor substrate-1 (IRS-1) gene have recently been suggested to contribute to the susceptibility of non-insulin-dependent diabetes mellitus (NIDDM). The purpose of this study was to examine the role of the IRS-1 missense mutations at codons 972 (glycine to arginine) and 513 (alanine to proline) in two diverse populations from South India and Finland at high risk for NIDDM. DNA was amplified and digested with restriction enzymes BstN1 to detect the codon 972 mutation and Dra III to detect the codon 513 mutation. The codon 513 mutation was not found in the study subjects. The codon 972 mutation was present in 10.3% of 126 middle-aged NIDDM subjects and 5.3% of 95 matched control subjects in the South Indians (p = 0.17). In elderly Finnish subjects the frequency of the mutation was 7.5% in 40 NIDDM subjects and 7% in 42 matched control subjects. The frequency of codon 972 mutation in the South Indian NIDDM subjects was very similar to the two previously published studies in Danish and French subjects although each study individually fails to reach conventional levels of significance. The data from all four ethnic groups were analysed together after ascertaining that significant heterogeneity did not exist between the studies. Overall, the frequency of the codon 972 mutation is found in 10.7% NIDDM subjects and 5.8% control subjects (p = 0.02). These studies suggest that the codon 972 mutation of the IRS-1 gene might act as a susceptibility gene predisposing to NIDDM in certain ethnic groups.

Proteinuria in NIDDM in south India: analysis of predictive factors

There are few data on the risk factors for diabetic nephropathy in the Asian Indian population, although several studies have shown a high prevalence of the disease in this ethnic group. This study also aimed to assess the role of hyperglycaemia and hypertension in the causation and course of nephropathy in this population, which has low rates of obesity. Retrospective analysis of two groups of non-insulin dependent diabetic (NIDDM) patients, one without proteinuria (< 100 mg/day, n = 25) and the other with proteinuria (> or = 500 mg/day, n = 25), matched for age, sex, duration of diabetes and body mass index (BMI) was done to study the factors predisposing to proteinuria and also its progression during a 2 year follow-up. Logistic regression analysis showed that the factors contributory to proteinuria were initial HbA1 and initial systolic blood pressure. The average proteinuria during the follow-up was dependent on the initial and average systolic and diastolic blood pressure values. No correlation was seen between cholesterol or triglyceride values and the change in proteinuria. Creatinine clearance deteriorated in the proteinuric group and this was related to the presence of proteinuria and initial diastolic blood pressure. This study emphasizes the importance of blood pressure in the progression of diabetic nephropathy, even in people who have low BMI. Therefore, good control of blood pressure has an important role to play in the management of this condition.

Family studies of non-insulin-dependent diabetes mellitus in South Indians

Though a genetic basis for non-insulin-dependent diabetes mellitus (NIDDM) is clear, the likely mode of inheritance is not known. The segregation of NIDDM was studied in 64 nuclear South Indian pedigrees (449 individuals) ascertained through an affected proband having both parents and more than 1 sibling alive and available for oral glucose tolerance testing. A high proportion of parents were found to be of abnormal glucose tolerance [89 of 128 (70%) diabetic and 11 of 128 (9%) impaired]. Complex segregation analysis was performed using (1) POINTER which implements the mixed model and distinguishes major gene, multifactorial and non-transmitted environmental contributions to affection and (2) COMDS which implements an oligogenic model with major gene, modifier gene and environmental contributions to a) affection and b) diathesis (an ordered polychotomy amongst non-affected family members, based on 2-h plasma glucose level). Using POINTER, there was no formal support for a major gene and the most parsimonious solutions were achieved with multifactorial models. Using COMDS, we found i) significant improvements in models when information on glucose levels in nondiabetic family members (diathesis) was included, ii) support for segregation of a diallelic gene as well as background familial resemblance, and iii) under the best-supported model, this diallelic locus featured incomplete dominance (d = 0.8) and a disease-predisposing allele frequency of 14%. In South Indians, segregation of NIDDM is inadequately described by simple major gene models: more complex models provide more satisfactory descriptions. This finding, if applicable in other populations, has important implications for the search for diabetes-susceptibility genes.

High prevalence of NIDDM and IGT in an elderly south Indian population with low rates of obesity

OBJECTIVE--To assess the prevalence of diabetes and impaired glucose tolerance (IGT) in the urban and rural elderly population in south India. RESEARCH DESIGN AND METHODS--Urban and rural populations > or = 60 years of age and representative of the areas (873 urban and 588 rural subjects) were screened for diabetes and IGT using fasting and 2-h postglucose capillary blood glucose measurements. RESULTS--In the urban area, 211 (23.7%) had diabetes, and 101 (12.4%) had IGT. In the rural area, 56 (9.9%) had diabetes, and 82 (14.9%) had IGT. The ratio of newly diagnosed to known diabetes was 1:3 in the urban and 1:1 in the rural areas. Positive family history of diabetes, body mass index (BMI), subscapular-to-triceps ratio, and waist-to-hip ratio were significantly associated with diabetes in the urban population. Only age and BMI showed significant association with diabetes in the elderly rural population. None of the tested parameters, except age in the urban subjects, showed association with IGT. CONCLUSIONS--This study highlights the high prevalence of glucose intolerance in elderly south Indians having low mean BMI (mean +/- SD; urban 21.7 +/- 4.6, rural 17.9 +/- 3.3 kg/m2). Although there was a twofold higher prevalence of diabetes in the urban area, the occurrence of IGT was similar in urban and rural populations.

Prevalence of proteinuria in non-insulin dependent diabetes

Proteinuria was estimated in 600 non-insulin dependent diabetes mellitus (NIDDM) patients in 24 hrs collection of urine. The test was repeated at least twice in a year to confirm the persistence of proteinuria. Mild proteinuria (200-500 mg/d) occurred in 94 (15.7%) and nephropathy (> 500 mg/d) in 112 (18.7%) patients. Nephropathy commonly occurred with long-standing diabetes (> 10 years). Development of proteinuria correlated directly with the duration of diabetes, diastolic and systolic blood pressure, age of the patients, serum creatinine and inversely with creatinine clearance. Retinopathy was seen in 75% of those with nephropathy. It is concluded that proteinuria occurs in one third of NIDDM patients and the risk of nephropathy increases with duration of disease.

Ofloxacin-containing combined drug regimens in the treatment of lepromatous leprosy

A total of 26 clinically diagnosed adult patients, with active untreated lepromatous leprosy, with a Bacteriological Index of 4+ or more, were admitted to the hospital of the Central Leprosy Teaching and Research institute, Chengalpattu, India, between 1989 and 1991. After prescribed investigations, the patients were randomly allocated in groups of 3 to 3 treatment regimens, namely: 1, clofazimine 50 mg daily and 300 mg once in 4 weeks + dapsone 100 mg daily (AA); 2, (AA)+ofloxacin 400 mg daily (BB); and 3, (AA)+ofloxacin 800 mg daily (CC). The drugs were administered for 56 days continuously under supervision. Sequential biopsy results on day 0, 7, 14, 28 and 56 in normal mouse footpad revealed no growth by day 28 and 56 in all patients treated with CC and BB regimens, respectively. Calculation of the proportion of viable Mycobacterium leprae through analysis of median infectious dose (ID50) showed significant differences on day 7 in the percentage of kill between the ofloxacin-containing regimens and the other. Moderate to marked clinical improvement has been observed in a significantly higher proportion of patients treated with ofloxacin-containing regimens. All the 3 regimens were well tolerated. No severe complications or side-effects to the drugs were noticed with any of the regimens that required any suspension of treatment or the administration of steroids. Addition of ofloxacin to the standard WHO recommended MDT regimen for multibacillary patients may reduce the present duration of therapy. Ofloxacin may also be considered as an alternative drug in rifampicin-resistant cases or where rifampicin is contraindicated.

Prevalence of diabetes in pregnant women--a study from southern India

This study was carried out to assess the prevalence of diabetes in southern Indian women during pregnancy. Nine hundred and fifty women having > or = 24 weeks of gestation, attending two general gynaecology centres for antenatal check-ups were screened. Initially, the screening test with 1-h plasma glucose sampling following 50 g glucose load was done and those with glucose values > or = 140 mg/dl were subjected to a 3-h oral glucose tolerance test (OGTT) with 100 g glucose load. Among the 950 women, 6 were known diabetic subjects. Of the other 944, 89 were positive on screening test and 67 of them reported for OGTT. Four were detected to have gestational diabetes mellitus (GDM) (O'Sullivan and Mahan's criteria). Therefore the prevalences of total diabetes and GDM were 1.19% and 0.56%, respectively.

Pancreatic beta cell function in normoglycaemic offspring of diabetic parents

The aim of the study was to look for any time-realted fluctuation in the pancreatic beta cell function in normal offspring of diabetic parents, over a period of three years. Serum insulin (IRI) and C-peptide (CP) responses to oral glucose were reevaluated three years after the initial study in 25 normoglycaemic offspring of conjugal Type 2 diabetic parents. The mean area under the curve of IRI (AUC IRI) response was higher than normal control value in the offspring at both time points (P < 0.01) and the two values did not differ much. The 2 hr IRI was also significantly higher (P < 0.05) than the control value. CP responses at both time points in the offspring did not differ from the mean control value. Wide fluctuations in the individual IRI were noted on follow-up despite similar plasma glucose response. Follow-up IRI was higher in 6, lower in 5 (+/- 25% of the initial) and remained unaltered in the other 4 offspring. The corresponding CP showed increased values in 3, decreased values in 5 and no change in 7 offspring. The fluctuations were nonuniform in nature among the individuals studied. Disparity between the IRI and CP responses were present in 5 offspring during the follow-up. This study thus shows that wide fluctuations in insulin responses occur even in the normoglycaemic offspring of diabetic parents.

Differences in plasma insulin responses in urban and rural Indians: a study in southern-Indians

Fasting and 2 h post glucose plasma immunoreactive insulin (fasting IRI and 2 h IRI) responses were measured in urban (n = 149) and rural (n = 40) individuals with normal glucose tolerance during an epidemiological survey. In this survey, 900 urban and 1038 rural subjects were screened for glucose intolerance by capillary blood sampling. The respective response rates were 91% and 88%. We had planned to collect venous blood for IRI estimation, i.e. from 180 urban and 200 rural subjects. The compliance for the same was poor from the rural subjects and therefore the number available for IRI estimation was small. The mean +/- SD ages of the urban and rural groups were similar (35.3 +/- 9.9 and 38.6 +/- 13.1 years, respectively). The rural population had lower body mass index (BMI) and subscapular:triceps ratio compared to the urban group (p < 0.001). The total calorie consumption was lower and physical activity was higher in rural population. Fasting and 2 h insulin values in urban population were 16.6 +/- 9.4 mU l-1 and 60.6 +/- 42.5 mU l-1 and in rural 6.7 +/- 5.1 mU l-1 and 32.4 +/- 27.8 mU l-1, respectively; the values being significantly lower in the rural population (p < 0.001). Multiple regression analysis showed that in urban population the fasting insulin was correlated to the BMI and the 2h IRI to 2 h glucose, BMI and the subscapular:triceps ratio. In the rural population, similar results were obtained, except in that the 2 h IRI was influenced by the gender also.(ABSTRACT TRUNCATED AT 250 WORDS)

Height at onset of insulin-dependent diabetes in children in southern India

A total of 250 children with insulin-dependent diabetes mellitus (IDDM), having age at onset of diabetes < or = 18 years were studied. Their height at onset of diabetes was compared with that of the normal age- and sex-matched control population. No differences were observed in the heights of the two groups of children. Therefore, our results were similar to that found in Japan and differed from the reports in European children with IDDM in whom an increased growth velocity was noted before the onset of IDDM.

Delayed onset of diabetes in children of low economic stratum--a study from southern India

Influence of the socioeconomic status on the age at onset of insulin-dependent diabetes mellitus (IDDM) was analysed in 614 patients who developed diabetes < or = 20 years. The peak occurrence was seen at 11 years in girls (n = 293). The boys (n = 321) showed multiple peaks between 11 and 18 years. In the urban patients (n = 463), the peak was at 11 years in contrast to a delayed peak at 18 years in the rural group (n = 151). When analysed with respect to the family income, the higher income group (HIG) (Rs > 2000/month) showed a sharp peak at 11 years whereas the lower income group (LIG) showed a peak at 18 years (chi 2 = 7.2, P = 0.007). The median body weight of the LIG was lower compared to the HIG. Although the exact cause for the delayed age at onset of IDDM in the rural or LIG is not known, it is likely to be a consequence of the lower socioeconomic and nutritional status (indicated by low body weight) and probably indicates the influence of environmental factors in the pathogenesis of the disease.

Fasting plasma glucose in the diagnosis of diabetes mellitus: a study from southern India

The usefulness of fasting plasma glucose (FPG) in the diagnosis of diabetes mellitus was assessed in Asian Indians in South India. Oral GTT values in 570 newly screened adults were studied. Taking the WHO criteria of 2 h plasma glucose (PG) of > or = 11.1 mmol l-1 for diagnosis of diabetes, the validity of a FPG of > or = 7.8 mmol l-1 cut off value for diabetes was assessed. Using the regression analysis, the correlations of the FPG to 2 h PG were examined. Among the 268 with 2h PG value of > or = 11.1 mmol l-1, 205 (76.5%) had FPG > or = 7.8 mmol l-1. Sensitivity of FPG was 76.5% for diagnosis of diabetes and its specificity was 99%. An exponential regression model gave the best fit for FPG vs 2 h PG and using the regression equation, the predicted FPG for a 2 h PG of 11.1 mmol l-1 was 7.05 mmol l-1. Sensitivity increased to 90.3% with FPG of 7.05 mmol l-1 while the specificity remained at 92%. It is concluded that in the south Indian subjects, the sensitivity for diagnosis of diabetes with FPG of > or = 7.8 mmol l-1 was 76.5%; and it increased to 90.3% with FPG of > or = 7.05 mmol l-1.

Positive association in the absence of linkage suggests a minor role for the glucokinase gene in the pathogenesis of type 2 (non-insulin-dependent) diabetes mellitus amongst south Indians

Mutations of the glucokinase gene have been implicated in the development of glucose intolerance in pedigrees with maturity-onset diabetes of the young. However, the contribution of the glucokinase gene to the aetiology of common Type 2 (non-insulin-dependent) diabetes mellitus is uncertain. We have studied the role of the glucokinase gene in the pathogenesis of Type 2 diabetes in South Indians, using both population-association and linkage methodology. A pair of CA-repeat sequences (GCK(3') and GCK(5')) straddling the glucokinase gene were employed as markers, each subject being typed using the polymerase chain reaction and polyacrylamide gel electrophoresis. Comparisons of allele frequencies at these markers were made between 168 Type 2 diabetic subjects and 70 racially-matched control subjects. No differences in allele frequencies were apparent at the GCK(5') marker; however, there were significant differences in allele frequencies at the GCK(3') marker between the Type 2 diabetic subjects and control subjects (chi 2 = 11.6, df = 3, p = 0.009) with an increase of the z allele (78.0% vs 66.4%) and a decrease of the z + 2 allele (13.7% vs 25.0%) amongst the diabetic subjects. Linkage between glucose intolerance and the glucokinase gene was studied in 53 nuclear pedigrees under a variety of genetic models. Linkage was excluded (lod score < -2) at a recombination fraction of zero under five of the ten models used and highly unlikely (-2 < lod score < -1) under the others. The combination of positive association and negative linkage suggests that glucokinase acts as a minor gene influencing the development of Type 2 diabetes within this population.

Maternal age and birth order of young IDDM patients. A study from southern India

OBJECTIVE

To assess the effects of maternal age and birth order on the risk of IDDM in Asian Indians.

RESEARCH DESIGN AND METHODS

Data from a diabetes registry in Madras, India, was used to find IDDM patients diagnosed before 20 yr of age. A questionnaire was used to elicit clinical details of subjects.

RESULTS

Children with mothers < or = 24 yr of age had a higher percentage of IDDM. Children with lower birth orders had a higher prevalence of IDDM.

CONCLUSIONS

The risk of IDDM in children is increased in children with lower birth orders, born of younger mothers.

Genetic epidemiology of NIDDM among Asian Indians

Prevalence of non-insulin-dependent diabetes (NIDDM) in India was reported to be 2.3% in the urban and 1.5% in the rural areas in the early 1970s by the Indian Council of Medical Research (ICMR). Recent studies both in the migrant Indians and in the native Indians have shown the prevalence to be much higher than the above values. Similar prevalence of NIDDM in the migrant and native Indians in affluent areas suggests that Indians as an ethnic group have a high genetic risk for diabetes. Our recent study in South India showed a high prevalence of diabetes in the urban area (8.2%) versus a low prevalence of 2.4% in the rural area. Age, urban-rural factor, body mass index (BMI) and the waist:hip ratio (WHR) were positively associated with diabetes. Interestingly, the prevalence of impaired glucose tolerance (IGT) was similar in urban and rural areas (8.7% and 7.8%, respectively) despite a four-fold lower prevalence of diabetes in the latter. The ratio of new to known diabetes was 1:2 in the urban and 3:1 in the rural areas. There was a male preponderance among Indian diabetic patients. Migration from rural to urban environment with changes in dietary habits and physical inactivity may have contributed to the increased prevalence of diabetes. A high rate of familial aggregation is noted in NIDDM in India and the genetic risk of NIDDM increases with increasing family history of diabetes. In the adult offspring of diabetic parents, hyperinsulinaemia and decreased insulin sensitivity are observed before the development of glucose intolerance.

Glucagon response to glucose load in offspring of conjugal type 2 diabetic parents in south India

Immunoreactive glucagon responses were measured in 21 normoglycaemic adult offspring of non-insulin dependent (Type 2) diabetic parents, in the fasting state and during an oral glucose tolerance test. In 7 of the 21 offspring, the mean fasting immunoreactive glucagon value was significantly lower than the control value (p < 0.001). In this group, glucose stimulation did not produce inhibition of immunoreactive glucagon secretion. The insulin response in this group was not significantly different from the values in the other study groups. In the other 14 offspring, the pattern of glucagon response to glucose stimulation was similar to controls. It is likely that this non-suppressive effect of glucose on immunoreactive glucagon in some of the "prediabetic" individuals is an early change in the alpha cell function during the natural history of non-insulin dependent diabetes in Asian Indian subjects.

The islet amyloid polypeptide gene and non-insulin-dependent diabetes mellitus in south Indians

Islet amyloid polypeptide (IAPP), otherwise called amylin, is the monomeric component of islet amyloid. Deposition of this amyloid is a characteristic feature of non-insulin-dependent diabetes mellitus in humans and may play a role in the pathogenesis of the disease. As such, abnormalities in the structure or expression of the IAPP gene might contribute to the inheritance of this condition. The IAPP gene was studied in a well-characterised population of 62 unrelated Dravidian subjects with non-insulin-dependent diabetes mellitus and 56 normal Dravidian controls, using a restriction fragment length polymorphism generated by PvuII digestion. Genotype and allele frequencies did not differ between diabetic subjects and controls. Taken together with recent findings in Europid and other racial groups, an abnormality of the IAPP gene is highly unlikely to represent a major gene for the development of non-insulin-dependent diabetes mellitus.

Prevalence of glucose intolerance in Asian Indians. Urban-rural difference and significance of upper body adiposity

OBJECTIVE

To evaluate the prevalence of NIDDM and IGT in the urban and rural areas in southern India.

RESEARCH DESIGN AND METHODS

Two populations of the same ethnic background, but different socioeconomic background were chosen for this study. Nine-hundred urban people and 1038 rural subjects were studied. Fasting and 2-h post-glucose capillary blood samples after a 75 g oral glucose load (WHO criteria) were obtained in these randomly selected adults (greater than or equal to 20 yr of age).

RESULTS

Using the WHO criteria, the prevalence of NIDDM, adjusted to the age of the respective general population, was 8.2% in the urban and 2.4% in the rural populations. The prevalence was 8.4 and 7.9%, respectively, in urban men and women, and 2.6 and 1.6% in rural men and women. The age-adjusted prevalence of IGT was 8.7 and 7.8% in the urban and rural areas, respectively. The prevalence of IGT was 8.8% in urban men and 8.3% in women; the corresponding values for rural men and women were 8.7 and 6.4%. The prevalence of NIDDM increased with age, markedly so in the urban people. The urban-rural difference was significant for NIDDM (chi 2 = 29.4, P less than 0.001) but not for IGT. In the urban population, 65% of the NIDDM patients were known cases, whereas in the rural area, the known cases accounted for only 24%. Bivariate analysis showed an association of BMI, STR, and WHR with prevalence of NIDDM plus IGT. In the multiple logistic regression analysis, age, BMI, STR, and WHR were associated significantly with glucose intolerance in the urban population, whereas only age was significant in the rural population. The best predictors of NIDDM were age, BMI, WHR, and urbanization.

CONCLUSIONS

The study showed a high prevalence of NIDDM in the urban southern Indian population. The prevalence of NIDDM in the same ethnic group in rural areas was significantly lower. The prevalence of IGT was similar in both populations. Upper body adiposity was a significant predictor of NIDDM in this population with low rates of obesity.

Prevalence of childhood diabetes in an urban population in south India

The objective of the study was to estimate the prevalence of insulin-dependent diabetes in children less than or equal to 15 years in an urban area in south India, by a population study. Three zones from the northeastern part of the city demarcated by the Directorate of Census were chosen. Ascertainment of the cases from these zones was made (a) by collecting data from the major hospitals and diabetes clinics by personal visit; (b) by questionnaire sent to medical practitioners in the area; and (c) from the chemists and druggists who sell insulin. Recommendations of the Diabetes Epidemiology Research International Registry Group were used. Thirty children with insulin-dependent diabetes with age at diagnosis less than or equal to 15 years were identified. The prevalence was 0.26/1000. The peak age at diagnosis was 12 years. This first population-based study of prevalence of insulin-dependent diabetes in south India shows that insulin-dependent diabetes is not rare. It is higher than reported from many other Asian countries.

Insulin responses to varying hyperglycaemia in newly diagnosed non-insulin dependent diabetic patients

The effect of varying degrees of hyperglycaemia on insulin secretion was studied in newly diagnosed non-insulin dependent diabetic patients, stratified according to the fasting plasma glucose values. Of the 116 patients studied, 62 were non-obese and 54 obese. Insulin response patterns during 2h oral glucose tolerance test were analysed in comparison with the values in weight matched control subjects and also with respect to the degree of hyperglycaemia. The effect of hyperglycaemia on beta cell secretion differed in obese and non-obese patients. In the non-obese, fasting insulin levels were within normal range even in those with severe hyperglycaemia while the corresponding values in response to glucose stimulation showed a decreasing pattern. In obese patients, even fasting immunoreactive insulin (IRI) value was decreased and with increasing hyperglycaemia the reduction in IRI response to glucose stimulation was of greater magnitude compared to non-obese patients. Thus the modulating effect of obesity on insulin secretion appears to disappear with development of hyperglycaemia. The insulinogenic index was low in all the diabetic patients.

Microalbuminuria in NIDDM patients in south India

Urinary albumin excretion (UAE) was estimated by radioimmunoassay in 316 non-insulin dependent diabetic patients (NIDDM), with diabetes for 10 or more years and proteinuria less than 150 mg/24 h. Albuminuria was determined in 24 h collection of urine in 259 patients but in the other 57, a random sample was used. The mean UAE was 23 +/- 45.3 (SD) micrograms/mg creatinine in the patients against 4.4 +/- 2.7 micrograms/mg in the controls (30). Ninety patients (28.5%) had microalbuminuria i.e., the UAE exceeded, 20 micrograms/mg creatinine. A higher percentage (31.7%) of men had microalbuminuria than women (23.6%). The presence of microalbuminuria was similar in the insulin-treated and in oral drug-treated patients (29.6% and 26.5% respectively). Stepwise multiple regression analysis using albumin/creatinine ratio as the dependent variable showed that factors such as blood pressure, blood glucose, HbA1, body mass index, sex, age, duration of diabetes and the association of vascular complications of diabetes did not have significant correlation to microalbuminuria. Creatinine clearance showed a significant inverse correlation to the albumin/creatinine ratio. Although the prevalence of microalbuminuria in NIDDM in this study is not significantly different from those reported from other countries, the morbidity index due to kidney disease could be high due to the large absolute number involved in our country. This underscores the need for early detection of the disease and institution of preventive measures to arrest its progression.

Nutritional profile of fibrocalculous pancreatic diabetes and primary forms of diabetes seen in southern India

Plasma levels of retinol binding protein (RBP), prealbumin, total protein, albumin, transferrin and ferritin were estimated in three groups of diabetic patients seen at a diabetes centre in S. India. The groups consisted of patients with fibrocalculous pancreatic diabetes (FCPD), non-insulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM). Mean RBP levels were lower in FCPD and IDDM patients compared to controls but this did not reach statistical significance. Prealbumin levels were normal in FCPD patients, but low in IDDM compared to controls (P less than 0.005) and NIDDM (P less than 0.05). FCPD patients had lower transferrin levels compared to controls (P less than 0.05). There were no differences in the levels of total protein, albumin and ferritin in any of the study groups. The study shows that biochemical evidence of undernutrition is seen in FCPD and IDDM patients while NIDDM patients are not significantly different from non-diabetic control subjects.

Anthropometric studies in diabetes in the Tropics

Anthropometric studies were carried out in three groups of diabetics seen in southern India, namely fibrocalculous pancreatic diabetes (FCPD) (n = 49) (a subtype of malnutrition related diabetes), insulin dependent diabetes mellitus (IDDM) (n = 55) and non-insulin dependent diabetes mellitus (NIDDM) (n = 104). Both FCPD and IDDM had significantly lower body mass index, skinfold thickness (triceps, biceps, subscapular and suprailiac), mid-arm circumference and fat mass compared to controls and NIDDM patients, (p less than 0.001 for all parameters). FCPD and IDDM males did not show any significant differences in any of the anthropometric parameters studied. Among the females, FCPD had lower triceps skinfold measurements (p = 0.007) and mid-arm circumferences (p less than 0.05) compared to IDDM patients. Patients with NIDDM did not show any significant difference compared to the control group. This study shows that both FCPD and IDDM patients have lower body mass and fat mass compared to NIDDM patients and control subjects.

Familial aggregation in type 1 (insulin-dependent) diabetes mellitus: a study from south India

An analysis of 617 Type 1 (insulin-dependent) diabetic patients from 587 families was made. In 33 families (5.6%) there was more than one Type 1 diabetic patient. In 98 families (16.7%) positive family history of Type 2 (non-insulin-dependent) diabetes was present. There was a linear correlation between the age at diagnosis of the proband and that of the sibling (r = 0.73, p less than 0.001) in the Type 1 multiplex families. The risk of Type 1 diabetes in relatives was found to be 2.7% by Li Mantel estimate, which is lower than that reported among Europeans. The cumulative risk was higher (p less than 0.001) in the relatives of Type 1 diabetic patients with age at diagnosis less than or equal to 10 years.

Comparative study of monocomponent insulins and conventional insulins on the course of diabetic nephropathy. A follow-up study

Two matched groups of insulin requiring non-insulin dependent diabetic (NIDDM) patients with mild proteinuria (200 to 999 mg/day), one on mono component (MC) insulin therapy and the other on conventional insulins were studied for a 3 year period to evaluate the course of nephropathy in these two groups. Twenty-seven and 35 patients were followed-up in the MC insulin and conventional insulin groups respectively. In the MC insulin treated group, the percentage of patients showing deterioration in proteinuria was lower (11% vs 34%, P less than 0.05) and the percentage showing improvement was higher (48% vs 29%) compared to the conventional insulin treated group. Insulin antibody titres decreased significantly in the MC insulin group and serum C-peptide values decreased in both groups on follow-up.

Changes in peripheral insulin concentrations in non insulin dependent diabetes during treatment. Assessment by mathematical applications

Serum immunoreactive insulin responses to meal stimulus were studied in 20 newly detected non insulin dependent diabetes mellitus patients, following one week of treatment with high carbohydrate, high fibre diet and glibenclamide. Ten patients showed "rapid glycaemic response" i.e. the glycaemic response was good within a week. The rest of them were called "slow responders". The insulin responses were heterogenous. Mathematical calculations using the glucose and insulin responses showed improved beta cell function and peripheral action of insulin in rapid responders. On the other hand, the slow responders showed only slightly improved beta cell function with no change in peripheral action of insulin. The second phase of the study constituted follow-up studies upto 6 months. The corrected insulin response (CIR) increased initially in several patients. The peripheral insulin action improved in all patients with longer duration of treatment and lower insulin concentrations were required to maintain normoglycaemia at this stage. The results of the study indicate that a) multiple factors influence glucoregulation, b) even short term effects of the drug appear to be mediated by extra pancreatic mechanisms, and c) the extrapancreatic action improves significantly on long term use of the drug.

Combination therapy of glibenclamide and insulin in NIDDM patients with secondary failure to oral drugs

A trial of combination therapy with glibenclamide + insulin was conducted in 26 patients with non insulin dependent diabetes mellitus (NIDDM) who had secondary failure to oral hypoglycaemic agents (OHA). Patients were included in the study if they failed to respond to a dose of 15 mg of glibenclamide under strict dietary regulations. Small doses of insulin were added until satisfactory glucoregulation was achieved. On withdrawal of the OHA, in 20 patients, the post-prandial plasma glucose values (PPBS) increased again by greater than or equal to 25%; they were considered as "responders". Responders were divided into two equal groups of alternate patients; group I was treated with insulin + glibenclamide and group II with insulin + placebo. The patients were then followed up at monthly intervals for 6 months. The dose of insulin required to maintain normal plasma glucose value was significantly lower (P less than 0.05) in group I. Fewer patients in group I needed two injections of insulin per day; however this difference was not statistically significant. Normalisation of serum triglyceride and lowering of HbA1 occurred in both groups. This study shows that addition of glibenclamide to insulin treatment is advantageous in NIDDM patients showing secondary failure to OHA.

Immunoreactive insulin and insulin degrading enzymes in erythrocytes. A preliminary report

Immunoreactive insulin (IRI) and insulin degrading enzyme activity (IDEA) of the plasma and the corresponding erythrocyte lysate were estimated in 21 normal volunteers, 18 non insulin dependent diabetic patients (NIDDM), and 16 insulin dependent diabetics (IDDM). The erythrocytes contained several-fold higher concentrations of IRI than in plasma, both in normal and diabetic subjects. The values in controls ranged from 80 to 458 uU/ml against a range of 5 to 25 uU/ml in the corresponding plasma samples. The IRI contents of the diabetic patients were also similar. It showed no correlation to the fasting plasma glucose or the plasma IRI. Following an oral glucose load, no change occurred in the IRI content of the erythrocytes, unlike the changes seen in plasma. The IRI content of the lysate increased with dilution of the sample. The IDEA was higher in diabetic patients compared to controls, especially so in the IDDM (P less than 0.01). It also showed more than one peak activity at different pH of the reaction buffer, indicating the possibility of a complex of enzymes. Human erythrocytes contain large pools of IRI and its degrading enzymes. The significance of the pool of the insulin in non-target tissue needs to be studied.

Decreased insulin sensitivity in offspring whose parents both have type 2 diabetes

Offspring of two Type 2 diabetic parents have a high prevalence of diabetes and impaired glucose tolerance. Studies in normoglycaemic offspring have shown abnormal insulin responses. Twenty-four non-obese offspring having normal oral glucose tolerance were investigated by the insulin tolerance test for abnormalities of insulin sensitivity. Plasma insulin responses were measured during an oral glucose tolerance test. Although the plasma glucose responses during the OGTT were similar to the control values, the corresponding insulin responses were higher. The mean area under the insulin curve was 121 +/- 29 (+/- SD) mU l-1 h in the control subjects and 203 +/- 73 mU l-1 h in the offspring (p less than 0.001). The mean KITT value in the offspring was 4.3 +/- 1.9 min-1 x 100 which was significantly lower (p less than 0.01) than the value of 6.2 +/- 2.0 min-1 x 100 in the control subjects. The results suggest that some offspring of two Type 2 diabetic parents have low insulin sensitivity and the presence of hyperinsulinism may be a compensatory phenomenon.

Plasma glucagon responses in tropical fibrocalculous pancreatic diabetes

Plasma insulin and glucagon responses to a glucose load were measured in a group of patients with fibrocalculous pancreatic diabetes (FCPD) and compared with patients with noninsulin-dependent diabetes mellitus (NIDDM) and control subjects. Both diabetic groups had markedly diminished insulin responses but the differences between FCPD and NIDDM groups were not significant. In control subjects, in response to the glucose load, plasma glucagon levels decreased while they increased in NIDDM patients. In FCPD patients there was no significant change in glucagon levels in response to the glucose load. The study shows that FCPD patients lack pancreatic alpha-cell responses to a glucose load. This may play a role in protecting these patients against ketosis.

Abnormalities in insulin response to intravenous glucose in offspring of conjugal (type 2) diabetic parents

Glucose and insulin responses were measured during intravenous glucose tolerance test in 12 normal controls and 16 normoglycaemic adult offspring of conjugal diabetic parents. The glucose response curve and the glucose disposal rate in the offspring were not different from the normal pattern. These subjects elicited a lower first phase insulin (0-10 minutes area under the curve, p = 0.04), lower peak immunoreactive insulin response (p = 0.032) and also showed a delay in the first phase (p = 0.037) compared to control values. The second phase of insulin (11-120 minutes area) was not significantly different in the two groups. These changes could serve as early markers of diabetes in offspring of conjugal diabetic parents.

Development of carbohydrate intolerance in offspring of Asian Indian conjugal type 2 diabetic parents

Sixty-four offspring of conjugal diabetic parents (OCDP) who were normoglycaemic initially were available for a retest after a period of 4-9 years. Among them 10 (15.6%) had developed diabetes, 19 (29.7%) had developed IGT and the remaining 35 (54.7%) had maintained normal GTT. The predictive value of the baseline (initial) parameters was tested. Among the non-obese OCDP (BMI less than 25 and less than 27 for women and men, respectively), the initial sum of plasma glucose (sigma PG), and the mean increment of insulin during GTT (delta IRI), and the 2-h IRI values were higher in the group that developed abnormal glucose tolerance (P less than 0.05 compared to controls and normal OCDP). They also had higher insulin:glucose ratios, indicating higher insulin output for a given glucose concentration. On the other hand, among the obese OCDP the initial parameters did not differ between those who developed abnormal glucose tolerance and those who did not. Stepwise multiple regression analysis showed that the baseline sigma plasma glucose value was significantly related to the final 2-h plasma glucose when all the OCDP were taken together (P = 0.0023) and also in the non-obese OCDP (P = 0.0002). The other parameter which showed a relation to the final 2-h plasma glucose was the baseline delta IRI, although it was not statistically significant (P = 0.08). No such relation was observed in the obese group.

Fibrocalculous pancreatic diabetes and obesity

Fibrocalculous pancreatic diabetes (FCPD) is a form of diabetes secondary to chronic pancreatitis that is found in tropical countries. Most patients with FCPD are lean and many are frankly undernourished. Four patients with FCPD who were obese are reported in this paper and this is the first report of obesity in FCPD patients.

Familial aggregation in tropical fibrocalculous pancreatic diabetes

There is very little information on the genetic factors associated with fibrocalculous pancreatic diabetes (FCPD). Ninety-eight first-degree relatives of FCPD patients were subjected to detailed studies, which included glucose tolerance tests, x-ray films of the abdomen, ultrasonography, and studies of exocrine pancreatic function. The study shows that there is a familial aggregation of FCPD with evidence of vertical transmission of the disease from parent to offspring in some families. Routine screening of families of FCPD probands helped to pick up cases in the stage of impaired glucose tolerance. There is heterogeneity in FCPD with respect to familial factors. Some families show marked familial aggregation of FCPD while in others the disease occurs either sporadically or in association with other family members who have abnormal glucose handling.