Prevalence and factors associated with abscess and scar formation at the site of Insulin injection among patients attending Diabetic clinics in selected public and private hospitals in Dar es salaam

Abstract

ABSTRACT Background: More than 530 million people live with diabetes worldwide, and in Tanzania, the prevalence of diabetes among adults is 12.3%. Insulin remains the cornerstone of therapy in all type 1 diabetic patients and a substantial number of patients with type 2 diabetes mellitus. Despite the increase in the number of insulin users, there is a shortage of data in Tanzania regarding its safety, particularly for skin-related adverse complications, including abscess formation and scarring at injection sites. Aim: This study aimed to assess the prevalence of abscess formation and scarring at insulin injection sites and to identify the determinants among diabetic patients on insulin therapy. Methodology: A hospital-based cross-sectional study was conducted, involving 428 randomly selected patients on insulin therapy from two selected public hospitals (Mwananyamala and Temeke regional referral hospitals) and two private hospitals (Shree Hindu Mandal and Hubert Kairuki Memorial Hospital) in Tanzania. Sociodemographic and clinical data were collected using a questionnaire. Data were analyzed using Stata version 15.0 software, and modified poison regression was employed to determine factors associated with abscess and scar formation among patients on insulin therapy. The variables with a p-value of <0.05 in the final model were considered the main factors associated with the abscess and scarring. Results: The study found the prevalence of abscesses and scars were 22.2% and 46.7% respectively. Factors associated with abscess included; improper injection technique (aPR= 1.11; 95%CI:1.02-1.21, p = 0.009), occupation (particularly self-employment) (aPR = 2.34; 95%CI:1.04-5.27, p = 0.4), and improper injection site rotation (aPR = 2.7; 95%CI:1.13-6.45, p = 0.025). The use of an insulin pen was observed to be protective from abscess formation at (aPR = 0.13; 59%CI:0.04-0.48, p = 0.002). Scars were observed to be influenced by improper site rotation (aPR = 1.63; 95%CI:1.03-2.32 P = 0.037), uncontrolled blood glucose level (aPR = 1.69; 95%CI:1.01-2.84, p = 0.049), the use of insulin and syringes obtained from other places apart from at facilities patients attended clinics (aPR = 2.51; 95%CI:1.22-1.98, p = 0.035) and occupation where the self-employed had more chances of developing scars (aPR = 2.0; 95%CI:1.21-3.33, p = 0.007) followed by those with the formal employment (aPR = 1.9; 95%CI:1.04-3.41, p = 0.036) when compared to the non-employed. Conclusion and recommendations: This study observed a high prevalence of abscesses and scars at injection sites among diabetic patients on insulin therapy. The factors associated with abscesses include improper injection technique, occupation(self-employment), and improper injection site rotation. The use of an insulin pen was protective against abscesses. Factors associated with the scars included improper site rotation, uncontrolled blood glucose, occupation, and sourcing insulin and syringes from the community drug outlets. Abscesses and scars adverse events can be mitigated if; healthcare staff provide education on proper injection techniques, site rotation, and regular blood glucose monitoring. The Ministry of Health, hospital management, and other stakeholders should ensure consistent supply and advocate using insulin pens. Community drug outlet healthcare staff should be trained on DM and its management to enable them to provide proper counseling to insulin users. There is a need for further studies on why occupation in particular self-employment is associated with abscesses and scars.