Studies on effects of insulin therapy on body weight and blood pressure in obese

type 2 diabetics

Sylvi Persson1, PhD, BSc, Hans Larsson2, MD, PhD,

1Department of Health Sciences and Social Work, University of Vaxjo, Sweden

2Department of Medicine / Endocrinology, Hospital of Varberg, Sweden

Background: Body weight tends to rise on institution of insulin therapy in type 2 diabetics. One possible reason is stimulated feelings of hunger but there may also be other reasons for this phenomenon.

Method: Blood pressure and body weight were studied in seventeen obese type 2 diabetics before start of insulin therapy and after two, four and six months on insulin. Blood glucose and lipids, HbA1C, S-bilirubin, S-electrolytes, S-enzymes were followed. Oral agents had proved to be insufficient.

Results: There was a significant rise of body weight (p<0,01) which seemed to level off after two months on insulin. Between four and six months on insulin there was only slight further weight gain. More surprisingly, a uniform increase of both diastolic and systolic blood pressure was seen after two months on insulin treatment (p<0,05). After four months blood pressure was back to pre-insulin values.

Conclusion: One explanation for the temporary increase of blood pressure could be effects of insulin on renal absorption of sodium as in insulin oedemas (Gupta et al 1992, Singh et al 1999). If so, insulin treatment may also to some extent increase body weight by enhancing retention of sodium and water. Further studies are needed for confirmation of our finding/results.