Nonadherence to insulin therapy in low-income, type 2 diabetic patients.
OBJECTIVE
To evaluate the psychosocial barriers to insulin use in low-income, type 2 diabetic patients; the clinical characteristics of these patients; and the possible causes of nonadherence to insulin regimens months after prescription.


METHODS
We studied a prospective cohort of low-income patients with type 2 diabetes mellitus, aged 45 to 75 years, attending a tertiary health care center in Mexico City, Mexico. Patients were eligible if their diabetes was not controlled with oral agents, and they were excluded if they had type 1 diabetes mellitus, a secondary cause of diabetes, had been admitted to the hospital within the month before study commencement, had been previously treated with insulin, had severe diabetic complications, or had a chronic or disabling medical illness. All patients were prescribed 6 to 10 units of neutral protamine Hagedorn insulin before bedtime and received a referral to visit with a diabetes nurse educator. The main outcome was adherence or nonadherence to insulin therapy, and it was correlated with several variables including attitudes toward insulin, diabetes self-management, diabetes-related knowledge, depression, and diabetes-related distress. Brief medical history, complete battery of questionnaires, and laboratory workup were obtained at baseline and 1 to 3 months after insulin prescription.


RESULTS
Twenty-nine consecutive patients were included. Mean age (+/- standard deviation) was 59 +/- 8 years, 18 (62%) were women, mean diabetes duration was 14 +/- 9 years, and mean hemoglobin A1c level was 10.8 +/- 1.4%. Negative attitudes toward insulin were very common, particularly in patients with less education and poorer diabetes-related knowledge (odds ratio, 6.2; 95% confidence interval, 1.04-47.3; P = .02). Even when they received precise recommendations, 12 patients (41%) did not adhere to insulin treatment. Patients who did not adhere to therapy were most commonly women and were depressed (P = .05). Improved adherence was significantly associated with the additional support of a diabetes nurse educator (odds ratio, 6.6; 95% confidence interval, 1.0-55.7; P = .02).


CONCLUSIONS
Improving patient perception and acceptance of insulin with the help of diabetes educators can facilitate earlier and more aggressive intervention and thus optimize glycemic control.
Lerman
Israel
I
Department of Endocrinology and Metabolism, National Institute of Medical Sciences and Nutrition Salvador Zubirán, Mexico City, Mexico. israellerman@gmail.com
Díaz
Juan Pablo Moreira
JP
Ibarguengoitia
Ma Elena Romero
ME
Pérez
Francisco Javier Gómez
FJ
Villa
Antonio R
AR
Velasco
Maria Luisa
ML
Cruz
Roberto Gómez
RG
Rodrigo
Juan Antonio Rull
JA
D000368:Aged; D001294:Attitude to Health; D015331:Cohort Studies; D003863:Depression / Q000523:psychology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000523:psychology*; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use*; D008297:Male; D055118:Medication Adherence / Q000208:ethnology / Q000523:psychology*; D008800:Mexico; D008875:Middle Aged; D010349:Patient Compliance / Q000208:ethnology / Q000523:psychology*; D011203:Poverty / Q000208:ethnology / Q000523:psychology*; D011446:Prospective Studies; D012189:Retrospective Studies; D012649:Self Concept; D012944:Social Support; D011795:Surveys and Questionnaires
D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin