Dataset Information

Beta cell function, insulin resistance and vitamin D status among type 2 diabetes patients in Western Kenya.

ABSTRACT: Serum vitamin D status exerts effects on glucose-insulin-homeostatic states underlying Diabetes-Mellitus, Type 2 (T2DM). This has been described in white and Asian population where low Vitamin D levels predicted future impairments in beta cell function and worsening of insulin resistance. This study aimed to examine the relationship between serum vitamin D, insulin resistance and beta cell function in a sub population of black Kenyan T2DM patients. The primary objective was to determine the levels of serum 25 hydroxy (25-OH) vitamin D, and estimate the insulin resistance, and beta cell function among T2DM patients at Moi Teaching and Referral Hospital (MTRH). This was a cross sectional study. 124 T2DM patients attending the MTRH Diabetes clinic between February and May 2016 were enrolled. Patients on insulin therapy and/or thiazolidinediones were excluded. Anthropometric, clinical and demographic data was obtained. Samples were drawn for estimation of serum 25-OH vitamin D, fasting insulin levels and fasting blood glucose levels. HOMA (Homeostatic model of assessment) model was used to estimate Beta cell secretion (HOMA-B) and insulin resistance (HOMA-IR); while the Disposition index {(DI) hyperbola product of insulin sensitivity (1/HOMA-IR) and beta cell secretion} was used to estimate the beta cell function. The relationships between serum vitamin D, insulin resistance and beta cell function were explored using a linear regression model. The study participants had a mean age of 56.2 (±?9.2) years, and a mean BMI of 26.9 kg/m² (4.3). Forty nine percent (n?=?61) were males. Vitamin D deficiency was present in 71.1% (n?=?88) of the respondents. Relatively low levels of insulin resistance and higher levels of beta cell dysfunction were observed {median HOMA-IR of 2.3 (0.7, 6.5) and Disposition Index (DI) of 25.5 (14.3, 47.2)}. Vitamin D levels exhibited a low positive correlation with DI [r?=?0.22 (95% CI: 0.03, 0.37)], but was not significantly correlated with HOMA-IR [r?=?0.07(95% CI:?-?0.11, 0.25)]. These results indicate that beta cell dysfunction rather than insulin resistance as the predominant defect among black T2DM patients seeking care at the MTRH diabetes clinic. Vitamin D deficiency is also prevalent among them and exhibits a low positive correlation with beta cell dysfunction. There was no correlation observed between Vitamin D deficiency and insulin resistance.

SUBMITTER: Said J

PROVIDER: S-EPMC7892854 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Beta cell function, insulin resistance and vitamin D status among type 2 diabetes patients in Western Kenya.

Said Jamil J Lagat David D Kimaina Allan A Oduor Chrispine C

Scientific reports 20210218 1

Serum vitamin D status exerts effects on glucose-insulin-homeostatic states underlying Diabetes-Mellitus, Type 2 (T2DM). This has been described in white and Asian population where low Vitamin D levels predicted future impairments in beta cell function and worsening of insulin resistance. This study aimed to examine the relationship between serum vitamin D, insulin resistance and beta cell function in a sub population of black Kenyan T2DM patients. The primary objective was to determine the leve ...[more]

PMID: 33602978

Similar Datasets

Project description:ObjectiveThis study evaluates insulin sensitivity, pancreatic beta-cell function (BCF), and the balance between the two in youth with type 2 diabetes and assesses the relationship of diabetes duration and HbA(1c) to insulin sensitivity and BCF.Research design and methodsThe subjects were 14 adolescents with type 2 diabetes and 20 obese control subjects of comparable age, BMI, body composition, and puberty. Insulin sensitivity was evaluated with a 3-h hyperinsulinemic (80 mU . m(-2) . min(-1)) euglycemic clamp. First-phase insulin secretion (FPIS) and second-phase insulin secretion (SPIS) were evaluated with a 2-h hyperglycemic (12.5 mmol/l) clamp. Fasting glucose rate of appearance was determined with the use of [6,6-(2)H(2)]glucose.ResultsFasting glucose rate of appearance was higher in type 2 diabetic patients than in obese control subjects (16.5 +/- 1.1 vs. 12.3 +/- 0.5 micromol . kg(-1) . min(-1); P = 0.002). Insulin sensitivity was lower in type 2 diabetic patients than in obese control subjects (1.0 +/- 0.1 vs. 2.0 +/- 0.2 micromol . kg(-1) . min(-1) per pmol/l; P = 0.001). Fasting insulin was higher in type 2 diabetic patients than in obese control subjects (289.8 +/- 24.6 vs. 220.2 +/- 18.0 pmol/l; P = 0.007), and FPIS and SPIS were lower (FPIS: 357.6 +/- 42.0 vs. 1,365.0 +/- 111.0 pmol/l; SPIS: 652.2 +/- 88.8 vs. 1,376.4 +/- 88.8 pmol/l; P < 0.001 for both). The glucose disposition index (GDI = insulin sensitivity x FPIS) was approximately 86% lower in type 2 diabetic patients than in obese control subjects. HbA(1c) correlated with FPIS (r = -0.61, P = 0.025) with no relationship to insulin sensitivity.ConclusionsDespite the impairment in both insulin sensitivity and BCF in youth with type 2 diabetes, the magnitude of the derangement is greater in BCF than insulin sensitivity when compared with that in obese control subjects. The inverse relationship between BCF and HbA(1c) may either reflect the impact of deteriorating BCF on glycemic control or be a manifestation of a glucotoxic phenomenon on BCF. Future studies in youth type 2 diabetes should target the natural course of beta-cell failure and means of retarding and/or preventing it.

Project description:BackgroundMalaria control in Kenya is based on case management and vector control using long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS). However, the development of insecticide resistance compromises the effectiveness of insecticide-based vector control programs. The use of pesticides for agricultural purposes has been implicated as one of the sources driving the selection of resistance. The current study was undertaken to assess the status and mechanism of insecticide resistance in malaria vectors in irrigated and non-irrigated areas with varying agrochemical use in western Kenya.MethodsThe study was carried out in 2018-2019 in Homa Bay County, western Kenya. The bioassay was performed on adults reared from larvae collected from irrigated and non-irrigated fields in order to assess the susceptibility of malaria vectors to different classes of insecticides following the standard WHO guidelines. Characterization of knockdown resistance (kdr) and acetylcholinesterase-inhibiting enzyme/angiotensin-converting enzyme (Ace-1) mutations within Anopheles gambiae s.l. species was performed using the polymerase chain reaction (PCR) method. To determine the agricultural and public health insecticide usage pattern, a questionnaire was administered to farmers, households, and veterinary officers in the study area.ResultsAnopheles arabiensis was the predominant species in the irrigated (100%, n = 154) area and the dominant species in the non-irrigated areas (97.5%, n = 162), the rest being An. gambiae sensu stricto. In 2018, Anopheles arabiensis in the irrigated region were susceptible to all insecticides tested, while in the non-irrigated region reduced mortality was observed (84%) against deltamethrin. In 2019, phenotypic mortality was decreased (97.8-84% to 83.3-78.2%). In contrast, high mortality from malathion (100%), DDT (98.98%), and piperonyl butoxide (PBO)-deltamethrin (100%) was observed. Molecular analysis of the vectors from the irrigated and non-irrigated areas revealed low levels of leucine-serine/phenylalanine substitution at position 1014 (L1014S/L1014F), with mutation frequencies of 1-16%, and low-frequency mutation in the Ace-1R gene (0.7%). In addition to very high coverage of LLINs impregnated with pyrethroids and IRS with organophosphate insecticides, pyrethroids were the predominant chemical class of pesticides used for crop and animal protection.ConclusionAnopheles arabiensis from irrigated areas showed increased phenotypic resistance, and the intensive use of pesticides for crop protection in this region may have contributed to the selection of resistance genes observed. The susceptibility of these malaria vectors to organophosphates and PBO synergists in pyrethroids offers a promising future for IRS and insecticide-treated net-based vector control interventions. These findings emphasize the need for integrated vector control strategies, with particular attention to agricultural practices to mitigate mosquito resistance to insecticides.

Dataset Information

Beta cell function, insulin resistance and vitamin D status among type 2 diabetes patients in Western Kenya.

Publications

Beta cell function, insulin resistance and vitamin D status among type 2 diabetes patients in Western Kenya.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets