Achieving good glycemic control is of paramount importance in the reduction of diabetes mellitus (DM) associated morbidity and mortality. Insulin plays a key role in the management of DM but unfortunately whilst some healthcare providers present insulin as a treatment of last resort , patients on insulin often have insulin related issues such as needle phobias, fear of hypoglycaemia, weight gain and in developing countries, costs. This Report aims at assessing insulin prescription pattern, insulin costs and issues associated with adherence.
This was a Cross-sectional observation Study whereby 160 patients with DM who were on insulin solely or in combination with oral hypoglycaemic agents were recruited over a 6 month period. Information obtained from the Study subjects pertained to their histories of DM, types of insulin, insulin costs, adherence issues and insulin delivery devices. Long and short term glycaemic control were determined and evaluated for possible relation to insulin adherence. Test statistics used were chi square, t test and binary regression.
Insulin adherence was noted in 123-77% of the Study subjects and this was comparable between persons with type 1 DM and those with type 2 DM. The mean glycosylated haemoglobin values were significantly higher in those who admitted to non insulin adherence compared to those who adhered to their insulin regimen (9.7% (2.3) Vs 8.6% (2.1), p = 0.01). Reasons proffered by Respondents for non insulin adherence included high costs-15(41%), inconvenience −15 (41%) and needle pain-79)18%. A greater proportion of persons who self injected insulin adhered to insulin prescriptions compared to those who did not self inject and thus had better glycaemic control. Shorter duration of DM and older age were found to be predictors of adherence to insulin prescription.
The monthly mean costs of insulin for those who earned an income was 5212.8 Nigerian naira which is equivalent to 33.1 US dollars and we estimated that persons on a minimum wage would spend 29% of their monthly income on the procurement of insulin.
Health related costs, age, duration of DM and insulin associated side effects are some of the factors implicated in adherence to insulin prescription.