Study design and period
Institutional based comparative cross-sectional study was conducted from March 01 to April 01.2021.
Study Area
This study was conducted in Bahir Dar the capital of Amhara national regional state in Ethiopia located approximately 578 km northwest of Addis Ababa. The city is located at the exit of the Abbay from Lake Tana at an altitude of 1,820 meters (5,970 ft) above sea level. There are three governmental hospitals in the city these are, Felege Hiwot referral hospital, Tibebe Gihon specialized hospital, and Adiss Alem hospital. It's estimated that the total number of individuals with type 2 DM in follow-up service in the three governmental hospitals is 6,500. On average approximately 650 individuals with type 2 DM are expected to come for follow-up within one month.
Source of population
The source population are all adult type 2 DM patients attending follow-up service in Bahir Dar governmental hospitals and the comparison groups are individuals who appear healthy in Bahir Dar governmental hospitals (patient accompanies in the medical OPD).
Study population
Type 2 DM patients who were attending follow-up service in Bahir Dar city selected governmental hospitals and available during the data collection period.
The comparison groups are non-DM individuals who appear healthy (patient accompanies in the medical OPD) in Bahir Dar selected governmental hospitals and available during the data collection period.
Inclusion and Exclusion criteria
Both type 2 DM and non-DM individuals aged ≥30 years were included in the study and individuals who were pregnant or lactating, seriously ill, and who had night-time shifts works were excluded.
Sample size determination and sampling producer
The sample size required for the first specific objective was calculated using Epi Info version 7.2 statistical software considering the proportion of poor sleep quality among individuals with type 2 DM (P1 = 55.6%) and comparison groups (P2 = 33.3%) from another similar study(14). By using a 95% confidence level and 80% power with the ratio of 1:1. This yields an initial sample size of 172. By considering a 10% non-response rate, 189 is the total sample size.
The sample size for the second specific objective was calculated using the following assumptions; CI=95%, power=80%, the ratio of unexposed to exposed =1;1, percent outcome in the exposed group (P1), and percent outcome in the unexposed group(P2) (Table 1).
Table 1. Sample size calculation
Independent variable
|
AOR
|
P1
|
P2
|
Sample size
|
Female (17)
|
2.5
|
87
|
73
|
278
|
Comorbidity (18)
|
1.87
|
62.3
|
47
|
352
|
Glycaemic control (19)
|
3.2
|
69
|
35
|
110
|
Accordingly, the sample size calculated by using the independent variable comorbidity was found to be the highest then after adding 10% non-response rate and 1.5 design effect 583 was taken as a final sample size for the study. Using 1; 1 ratio 291 diabetic individuals and 292 non-diabetic individuals.
Two-stage cluster sampling was used. The three study hospitals were considered as clusters then from the three clusters two hospitals (Felege Hiwot referral hospital and Tibebe Gihon specialized) were selected. Individuals with type 2 DM were selected using systematic random sampling. The sampling interval was determined by dividing the expected number of diabetic individuals who come to the hospitals within one month (550) by the sample size of cases (292) then it gives a sampling interval of two then individuals were selected every 2ndunit. Non-DM individuals were also selected using a systematic random sampling technique. The expected number of patients accompanies in medical OPD within one month was 900. The sampling interval was determined by dividing the expected number of patients accompanies in medical OPD who come to the hospitals within one month (900) by the sample size of the comparison group (291) so every 3rdunit patient accompanies in OPD were interviewed.
Operational definitions
Sleep quality; The Pittsburgh Sleep Quality Index classifies a global score of > 5 as indicating clients have poor sleeping quality, whereas a global score ≤ 5 is classified as good sleeping quality(20).
Depression; A total score of PHQ‐9 score ≥10 points indicated major depression symptoms (21).
Social support; The Oslo social support index classifies a score of 3 to 8 as "poor support", 9–11 is "moderate support" and 12–14 is "strong support"(22).
Current smoker; Someone who smoked greater than 100 cigarettes in their lifetime and had smoked in the last 28 days(23).
Alcohol consumption; Alcohol use disorder identification test (AUDIT) score >8 indicates hazardous alcohol consumption(24).
BMI; A person was classified as underweight (BMI < 18.5 kg/m2), normal body weight (BMI 18.5−24.9 kg/m2), overweight (BMI 25–29.9 kg/m2), or obese (BMI ≥ 30 kg/m2)(25).
Good glycaemic control: A 3-month average fasting blood glucose measurement of the three consecutive visits was between 70 and 130 mg/dL(26).
Poor glycaemic control; Patients whose average fasting blood glucose measurements of the three consecutive visits was above 130 or below 70 mg/dl(26).
Comorbidity; a chronic disease that coexisted with their diabetes were considered to be comorbid(27).
Data collection tools and instrument
The English version questionnaire was translated into a local language Amharic. Three clinical nurses were recruited for data collection and one BSC nurse for supervision. The data collectors and the supervisor were trained for 2 days regarding the objective of the study and data collection procedure.
Structured questionnaires comprise Socio-demographic characteristics, a clinical characteristic checklist, sleep quality assessment, depression assessment, social support assessment, and physical activity assessment tool.
Using a digital glucometer, the blood glucose level of comparison group was assessed. The blood glucose result of RBS between 70 to 110 was considered as DM free.
Sleep quality was assessed using the Amharic version of PSQI. The PSQI comprises 19 self-rated questions that generate seven component scores (subscales). Each component scores 0–3 points. A score of “0” is “no difficulty,” while a score of “3” is “severe difficulty.” The total scores of seven components are added to yield one “global score,” which ranged from 0 to 21 points (20). It is validated in Ethiopia (Cronbach alpha of 0.6) (28). The reliability of the tool was tested by similar studies conducted in Ethiopia (19, 29).
Depression symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9). The PHQ-9 contains nine self-rated questions and the total scores ranged from 0 to 27 points(21). It is validated in Ethiopia with a Cronbach alpha of 0.81 (30).
Social support was assessed by using Oslo 3-item Social Support Questionnaire. The sum of the Oslo 3-items social support score was ranged from 3 to 14 (22). It is also validated (22). The reliability of the tool is tested by another study conducted in Ethiopia(31).
The international physical activity questioners (IPAQ) were used to assess the physical exercise of participants. Using the IPAQ scoring protocol to considered participants into high, moderate, and low levels of physical activity categories(32). The reliability of the questioner tested by another study in Ethiopia(33).
Alcohol consumption was assessed using the alcohol use disorder identifier test (AUDIT). It is a 10-item questionnaire that covers the domains of alcohol consumption, drinking behavior, and alcohol-related problems(34). The AUDIT was also validated in Ethiopia (Cronbach's α = 0.84) (35).
BMI: participants were weighed in kg by using a digital weight scale in light clothing. Height was measured using a measuring tape; participants positioned their feet together, feet flat on the ground, with flat shoes, and it was recorded to the closer 0.5 cm. Body mass index was calculated as the ratio of weight in kilograms to the square of height in meters.
Data processing and analysis
First, the data were checked for completeness then coded and entered using EPI-data version 3.1. The data were exported to Statistical Package for Social Science (SPSS) version 20 software for analysis. The data were then re-coded and cleaned. Multicollinearity was checked using variance inflation factor (VIF) and the VIF of each variable was <5. Model fitness was checked for the three models using the Homer–Lemeshow goodness of fit test and the p-value for all three models were <0.05. Descriptive and summary statistics were carried out to determine the prevalence and percentage of variables. Chi-square tests were also used for comparison. Bi-variable and multivariable logistic regression analyses were used to identify associated factors. Those variables with a p-value less than 0.25 in the bi-variable analysis were entered into the multivariable analysis. In multivariable logistic regression variables with a p-value, less than 0.05 with a 95% confidence interval were considered as significantly associated with outcome variables.
Ethical approval and consent to participate
The ethical approval was obtained from the institutional review board of Bahir Dar University, college of medicine, and health science. Written informed consent was taken from participants after the purpose of the study was clearly explained. Study participants have the right to withdraw from the study at any point in time. The information collected from the participants was used for research purposes only. To keep confidentiality, the collected information was kept in a file without a personal identifier of the study participant. Individuals with poor sleep quality and Participants that found to be at risk of depressive symptoms were referred to a psychiatric evaluation in the hospital. This study was conducted following the ethical standard of the declaration of Helsinki.