This was a Cross sectional observational study carried out at the Diabetic Centre of the Lagos State University Teaching Hospital, (LASUTH), Lagos State. Persons living with diabetes mellitus who were on insulin treatment (for at least a period of one month) solely or in combination with oral hypoglycaemic agents and who gave their consent were recruited.
Ethical approval for the study was obtained from the Lagos State University Teaching Hospital.
Participants provided information on their diabetes history, management and problems associated with management. The type of insulin in use, the number of daily injections, issues with adherence were ascertained from the Case folders, patient interview and prescriptions. Gainful employment where present was noted and the monthly income for those who earned a salary was documented.
Clinical examination was carried out basically to determine the anthropometric indices.
Long term and short term glycaemic control was evaluated for using glycosylated haemoglobin and fasting plasma glucose assessment respectively.
Good long term glycaemic control referred to HbA1c level of ≤6.5% .
Short term glycaemic control referred to FPG levels of ≤110 mg% .
Type 2 DM-Patients were classified as having type 2 diabetes mellitus using clinical criteria such as a present/prior history of usage of oral hypoglycaemic agents or usage of combination of insulin and the oral hypoglycaemic agents .
Type 1DM- This referred to patients who are presently on insulin and have been insulin requiring since diagnosis .
Information on insulin adherence was provided by the patients and their family members.
Insulin adherence was defined as “taking medication as prescribed and/or agreed between the patients and the health care provider over a period of one month”.
The “adherence rate” for the Study subjects referred to the proportion of patients who used insulin as prescribed over a period of one month.
Non adherence referred “not taking medication as prescribed and/or agreed between the patients and the health care provider over a period of one month”.
Insulin costs (direct cost) per month was determined through patient’s interview. Information on the number of vials or penfills of insulin and costs per month was obtained from the patient. Costs of insulin were calculated in Nigerian Naira (NGN) and converted to US dollars (USD) and the prevailing currency exchange rate was 150NGN to 1USD.
The proportion of income spent on insulin was calculated by the following formula:
(The prevailing minimum wage was 18,000 NGN or 120 USD)
SPSS was used for statistical analyses and a p value of ≤ 0.05 was deemed to be significant.