Khalida Iqbal 1, Najmul Islam 2, Naseema Mehboobali 1, Ali Asghar 2, Saleem P Iqbal 3, Mohammad Perwaiz Iqbal 1 Departments of Biological & Biomedical Sciences 1 Medicine 2 and Community Health Sciences 3, Aga Khan University Relationship of socio-demographic factors with serum levels of vitamin D in a Pakistani population of diabetic patients and healthy controls

Insufficiency of vitamin D is a global health problem, especially in developing countries of South Asia In Pakistan, it varies from 69-90% in various study populations Studies carried out in the West, have shown association of certain socio- demographic factors with vitamin D deficiency/insufficiency Very few studies have been carried out to investigate the relationship of socio-demographic factors with hypovitaminosis D [25(OH) vitamin D levels < 20 ng/ml] in this region

To investigate the prevalence of vitamin D deficiency in a hospital- based Pakistani population To investigate the role of socio-demographic factors with vitamin D status in this population of patients suffering from diabetes mellitus and age-matched healthy controls

Demographic characteristics of the two groups were determined using a questionnaire We recruited 111 adult patients with diabetes mellitus (age range years); 76 males and 35 females from the Endocrinology Clinics of the Aga Khan University Hospital with informed consent Additionally, 116 age-matched (within 5 years) healthy controls were also recruited from the personnel of the Aga Khan University and other health-care institutions in Karachi Serum levels of 25(OH) vitamin D were determined using kit methods

Vitamin D status in terms of 25 Hydroxy vitamin D levels DeficientInsufficientSufficientToxic levels <20ng/ml20-30ng/ml>30ng/ml>100ng/ml

Table 1: Demographic and clinical characteristics of Pakistani population of patients suffering from diabetes mellitus(n=111) and age-matched healthy controls(n=116) Variablen(%)Mean ± SD Gender Males 182(80.2) Females 45(19.8) Age (Years) 45.5±7.8 BMI (Kg/m 2) 26.8±5.0 Waist Circumference (cm) 95.8±10.2 Vitamin D levels (ng /ml) 18.26±13.8

Vitamin D status in the study population ng/ml<20 ng/ml >30 ng/ml

Table2: Frequency of ethnic groups in the study population Ethnicityn (%) Punjabi25(11.0) Sindhi42(18.5) Balochi4(1.8) Pathan17(7.5) Urdu78(34.4) Others59(26.0)

Table 3: Vitamin D status in different ethnic groups in the study population Ethnicity Vitamin D Deficient (<20ng/ml) Vitamin D Insufficient (21-30ng/ml) Vitamin D Sufficient (>30ng/ml) Punjabi17(68.0)4(16.0) Sindhi19(47.5)11(27.5)10(25.0) Balochi3(75.0)1(25.0)0(0) Pathan9(60.0)2(13.3)4(26.6) Urdu58(75.3)8(10.3)11(14.2) Others37(63.7)9(15.5)12(20.6)

Figure 1: Mean ± SD serum levels of Vitamin D with respect to monthly household income Monthly Household Income

Table 4: Association of Vitamin D deficiency with monthly household income * Monthly household income Crude OR (95% Cl)Adjusted OR (95% Cl) 1 Adjusted OR (95% Cl) 2 >Rs <Rs ( )2.32( )2.26( ) 1=adjusted for BMI 2=adjusted for waist circumference * : Logistic regression was used to study association

There is an association between monthly household income and vitamin D levels in this population There is high prevalence of vitamin D deficiency (65%) in a hospital- based Pakistani population Odds of vitamin D deficiency were more than 2-fold in the group having monthly household income less than Rs 50,000 compared to the group with monthly house-hold income more than Rs 50,000 Odds remain nearly the same even when the model was adjusted for BMI or waist circumference