Prevalence and Correlates of Vitamin D Deficiency Among Children and Adolescents From a Nationally Representative Survey in India

Objective: To evaluate the prevalence of vitamin D deficiency (VDD) and its correlates among apparently healthy children and adolescents. Methods: We carried out a secondary analysis of data of Comprehensive National Nutrition Survey 2016-18 to analyze the pre-valence and predictors of VDD among Indian children and adolescents. Results: The over-all prevalence of VDD in preschool children (1-4 years), school age (5-9 years) children, and adolescents (10-19 years) was 13.7%, 18.2%, and 23.9%, respectively. Age, living in urban area, and winter season were significantly associated with VDD. Vegetarian diet and high-income households were the main risk factors observed in 5-19 years age category. Female sex and less than three hour of physical activity/week were independent risk factors among adolescents. Conclusion: The prevalence and determinants of VDD across different age-groups are reported, and these should be interpreted and addressed to decrease the burden of VDD in India.

Performance of equations for estimation of 24-hour urinary sodium from morning fasting urine samples in a multisite study in India

BACKGROUND Dietary salt intake is an important modifiable risk factor for cardiovascular diseases. Estimation of 24-hour salt intake using morning urine samples needs to be validated in the Indian context. We examined the performance of INTERSALT, Tanaka and Kawasaki equations for the estimation of 24-hour urinary sodium from morning fasting urine (MFU) samples. METHODS We enrolled 486 adults aged 18–69 years from four regions of India with equal rural/urban and sex representation to provide 24-hour urine samples. The next day, a MFU sample was obtained. Based on the volume and sodium content of the 24-hour urine sample, 24-hour sodium excretion (reference method) was calculated. Sodium levels in the MFU samples were measured along with other parameters required, and the above equations were used to estimate 24-hour urinary sodium levels. Intraclass correlation coefficient (ICC) was used to assess the degree of agreement between the estimates from the reference method and the three equations. Bland–Altman (BA) plots were used to identify systematic bias and limits of agreement. A difference of 1 g of salt (0.39 g of sodium) between the mean salt intake by 24-hour urine and as estimated by equations was considered acceptable. RESULTS A total of 346 participants provided both the samples. The mean (SD) daily salt intake estimated by the 24-hour urine sample method was 9.9 (5.8) g. ICC was low for all the three equations: highest for Kawasaki (0.16; 95% CI 0.05–0.26) and least for Tanaka (0.12; 0.02–0.22). Only Tanaka equation provided estimates within 1 g of measured 24-hour salt intake (–0.36 g). BA plots showed that as the mean values increased, all the three equations provided lower estimates of salt intake. CONCLUSION Tanaka equation provided acceptable values of 24-hour salt intake at the population level. However, poor performance of all the equations highlights the need to understand the reasons and develop better methods for the measurement of sodium intake at the population level.

Cystatin C-based Glomerular Filtration Rate Estimating Equations in Early Chronic Kidney Disease.

Objective: To Compare performance of combined creatinine and cystatin C-based equation with equations based on either cystatin C or creatinine alone, in early chronic kidney disease. Design: Diagnostic accuracy study. Setting: Tertiary-care hospital. Patients: One hundred children with chronic kidney disease who underwent 99mTc diethylenetriamine pentaacetic acid (DTPA) glomerular filtration rate measurement. Methods: Estimating equations for glomerular filtration rate (GFR) based on serum cystatin C alone and in combination with serum creatinine were generated using regression analyses. These equations and the creatinine-based equation [0.42 x height/creatinine] were validated in 42 children with glomerular filteration rate between 60 and 90 mL/min/1.73 m2. Bias, precision and accuracy of estimating equations using DTPA glomerular filteration rate as gold standard. Results: Cystatin C-based equation (GFR=96.9 - 30.4 x cystatin) overestimated while the combined cystatin C-and creatininebased equation [GFR=11.45 x (height/creatinine) 0.356 x (1/ cystatin) 0.188] underestimated the measured GFR. Cystatin Cbased equation had less bias (1.9 vs. 12.4 ml/min/1.73 m2), and higher precision (13.1 vs. 25.6 mL/min/1.73 m2) and accuracy (92.1% vs. 75.7%) than creatinine-based equation. The combined cystatin C and creatinine equation had bias (-1.4 mL/ min/1.73 m2) precision (15.2 mL/min/1.73 m2) and accuracy (91.2%) similar to cystatin C-based equation. Conclusions: Cystatin C-based equation has a better performance in estimating glomerular filtration rate than creatinine-based equation in children with early chronic kidney disease. Addition of creatinine equation does not improve the performance of the cystatin C-based equation.

Analysis of the Stability of Urea in Dried Blood Spots Collected and Stored on Filter Paper

The ability to use dry blood spots (DBSs) on filter paper for the analysis of urea levels could be an important diagnostic tool for areas that have limited access to laboratory facilities. We developed a method for the extraction and quantification of urea from DBSs that were stored on 3M Whatman filter paper and investigated the effect of long-term storage on the level of urea in DBSs. DBSs of 4.5 mm in diameter were used for our assay, and we determined the urea levels in blood using a commercially available enzymatic kit (UV GLDH-method; Randox laboratories Ltd., UK). The DBSs on filter discs were stored at 4degrees C or at 37degrees C for 120 days. The mean intra- and inter-assay coefficient of variance for our method of urea extraction from dried blood was 4.2% and 6.3%, respectively. We collected 75 fresh blood samples and compared the urea content of each fresh sample with the urea content of DBSs taken from corresponding fresh blood samples. Regression analysis reported a regression coefficient (r) value of 0.97 and a recovery of urea from dried spots was 102.2%. Urea concentrations in DBSs were stable for up to 120 and 90 days when stored at 4degrees C and 37degrees C, respectively. Our results show that urea can be stored and quantitatively recovered from small volumes of blood that was collected on filter paper.

Analysis of the Stability of Urea in Dried Blood Spots Collected and Stored on Filter Paper

The ability to use dry blood spots (DBSs) on filter paper for the analysis of urea levels could be an important diagnostic tool for areas that have limited access to laboratory facilities. We developed a method for the extraction and quantification of urea from DBSs that were stored on 3M Whatman filter paper and investigated the effect of long-term storage on the level of urea in DBSs. DBSs of 4.5 mm in diameter were used for our assay, and we determined the urea levels in blood using a commercially available enzymatic kit (UV GLDH-method; Randox laboratories Ltd., UK). The DBSs on filter discs were stored at 4degrees C or at 37degrees C for 120 days. The mean intra- and inter-assay coefficient of variance for our method of urea extraction from dried blood was 4.2% and 6.3%, respectively. We collected 75 fresh blood samples and compared the urea content of each fresh sample with the urea content of DBSs taken from corresponding fresh blood samples. Regression analysis reported a regression coefficient (r) value of 0.97 and a recovery of urea from dried spots was 102.2%. Urea concentrations in DBSs were stable for up to 120 and 90 days when stored at 4degrees C and 37degrees C, respectively. Our results show that urea can be stored and quantitatively recovered from small volumes of blood that was collected on filter paper.

Impact of comprehensive cardiovascular risk reduction programme on risk factor clustering associated with elevated blood pressure in an Indian industrial population.

Background & objectives: Cardiovascular risk factors clustering associated with blood pressure (BP) has not been studied in the Indian population. This study was aimed at assessing the clustering effect of cardiovascular risk factors with suboptimal BP in Indian population as also the impact of risk reduction interventions. Methods: Data from 10543 individuals collected in a nation-wide surveillance programme in India were analysed. The burden of risk factors clustering with blood pressure and coronary heart disease (CHD) was assessed. The impact of a risk reduction programmme on risk factors clustering was prospectively studied in a sub-group. Results: Mean age of participants was 40.9 ± 11.0 yr. A significant linear increase in number of risk factors with increasing blood pressure, irrespective of stratifying using different risk factor thresholds was observed. While hypertension occurred in isolation in 2.6 per cent of the total population, co-existence of hypertension and >3 risk factors was observed in 12.3 per cent population. A comprehensive risk reduction programme significantly reduced the mean number of additional risk factors in the intervention population across the blood pressure groups, while it continued to be high in the control arm without interventions (both within group and between group P<0.001). The proportion of ‘low risk phenotype’ increased from 13.4 to 19.9 per cent in the intervention population and it was decreased from 27.8 to 10.6 per cent in the control population (P<0.001). The proportion of individuals with hypertension and three more risk factors decreased from 10.6 to 4.7 per cent in the intervention arm while it was increased from 13.3 to 17.8 per cent in the control arm (P<0.001). Interpretation & conclusions: Our findings showed that cardiovascular risk factors clustered together with elevated blood pressure and a risk reduction programme significantly reduced the risk factors burden.

Profile of biochemical risk factors for non communicable diseases in urban, rural and periurban Haryana, India.

BACKGROUND: Globalisation and increasing urbanisation in most developing countries including India raises concerns of possibility of a major increase in NCDs in these countries. WHO has recommended a STEPwise approach for NCD risk factor surveillance since risk factors of today are diseases of tomorrow. This paper presents the estimation of biochemical risk factors for NCDs undertaken as a part of the ICMR six centre study. OBJECTIVE: To estimate the prevalence and levels of bio-chemical risk factors (fasting blood glucose, total cholesterol, HDL and triglyceride levels) in urban, rural and periurban locations in Ballabgarh, Haryana. METHODOLOGY: A community based cross-sectional study was carried out in urban, rural and periurban areas. A total of 1513 subjects were enrolled (501 in urban, 504 in periurban and 508 in rural areas) with equal distribution by area of residence, sex and age group. Fasting blood glucose and lipids were estimated using enzymatic kits. RESULTS: The mean levels of fasting blood glucose, cholesterol, TGL and low HDL were the highest in the urban area, though there was not much difference in the rural and periurban areas. There was also an increasing trend of all the parameters as age increased in both men and women. 11.4% of men in urban areas had fasting blood glucose above the cut off levels and 44.3% of urban men and women had high cholesterol levels. CONCLUSION: This study documents a high burden of biochemical risk factorsnot only in urban areas but also in the periurban and rural population. It has also brought out some technical and operational issues for carrying out biochemical risk factors surveillance in the community. There is a need to scale up from surveys to surveillance mode using appropriate tools and application of this information for policy planning and programme implementation.

Cardiovascular risk factor prevalence among men in a large industry of northern India.

BACKGROUND: Industrial settings, with their intramural resources and healthcare infrastructure, are ideal for initiating preventive activities to increase the awareness and control of cardiovascular diseases (CVD). However, there are no reliable estimates of CVD and risk factor burden, nor of its awareness and treatment status in urban Indian industrial settings. We aimed to evaluate the prevalence of CVD and its risk factors, and to assess the status of awareness and control of CVD risk factors among a large industrial population of northern India. METHODS: We conducted a cross-sectional survey among all employees aged 20-59 years of a large industry near Delhi (n=2935), to evaluate their cardiovascular risk profile--by employing a structured questionnaire and clinical and biochemical estimations. The presence of coronary heart disease was ascertained by evidence of its treatment, Rose angina questionnaire and Minnesota coded electrocardiograms. RESULTS: The results for 2122 men, in whom complete information was available, are reported here. The mean age was 42 years and 90% of the men were below 50 years of age. The prevalence of major CVD risk factors (95% CI) was: hypertension 30% (28%-32%), diabetes 15% (14%-17%), high serum total cholesterol/HDL ratio (> or = 4.5) 62% (60%-64%) and current smoking 36% (34%-38%). Forty-seven per cent of the respondents had at least two of these risk factors. Another 44% (95% CI: 42%-46%) had pre-hypertension (INC VII criteria) and 37% (95% CI: 35%-39%) had evidence of either impaired fasting glucose or impaired glucose tolerance. Thirty-five per cent (95% CI: 33%-37%) of the individuals were overweight (BMI > or = 25 kg/m2) while 43% (95% CI: 40%-45%) had central obesity (waist circumference >90 cm). The metabolic syndrome was present in 28%-35% of the individuals depending on the diagnostic criteria used. The prevalence of several risk factors and the metabolic syndrome was high with increasing age, BMI and waist circumference. A third of those who had hypertension (31.5%) and diabetes (31%) were aware of their status. Among those aware, adequate control of blood pressure and blood glucose was present in only 38% of those with hypertension and 31% of those with diabetes, respectively. Coronary heart disease was present in 7.3% of the individuals while 0.3% had a history of stroke. CONCLUSION: This study demonstrates the high prevalence of CVD and its risk factors against a background of poor awareness and control among a comparatively young male population in a north Indian industrial setting.