Restless Leg Syndrome and Sleep Quality in Diabetic Patients with and without Neuropathy

Background: Restless legs syndrome (RLS), is a condition of uneasy feeling with an uncontrollable urge to move legs. This study was conducted to compare the frequencies of restless leg syndrome and sleep quality in diabetic patients with and without neuropathy. Methods: The comparative cross-sectional was conducted from February to June 2021 at Riphah College of Rehabilitation and Allied health sciences in collaboration with Pakistan Railway Hospital, Rawalpindi. A total of 271 participants were taken after informed consent. Pittsburgh Sleep Quality Index and Restless Leg Syndrome-Disability Index scale were used for assessing the quality of sleep and RLS in all participants, respectively. The relationship between the quality of sleep in diabetic patients with and without neuropathy was assessed by one-way ANOVA. Results: Out of 271 diagnosed cases of diabetes mellitus, 65 (23.9%) were males and 206 (76%) were females. A signiﬁcant relation ( p <0.05) between restless leg syndrome in diabetic patients with neuropathy (2.65 ± 1.36) was observed compared to diabetic patients without neuropathy (1.20 ± 1.44) with p < 0.01. A signiﬁcant relationship was also found between the quality of sleep in diabetic patients with neuropathy (1.87 ± 0.33). Conclusion: Restless leg syndrome is common in diabetic patients ( p <0.05) with neuropathy compared to diabetic patients without neuropathy and sleep quality equally deteriorated in diabetic patients regardless of neuropathy.


INTRODUCTION
Restless leg syndrome (RLS) is a sensorimotor sleep-related movement disorder characterized by a strong desire to move one's legs and an uncomfortable sensation in the lower extremities 1 . The prevalence of RLS in the general population is 5 to 15% 2,3 . The unpleasant sensation in the legs improved with movement. Restlessness in the legs gets worse during sleep or at rest making sleep initiation or maintenance more difficult. Thus, sleep disturbances occur in persons who suffer from this illness, resulting in daytime exhaustion, poor energy, irritability, and depression 4 . RLS can have a substantial negative impact on one's quality of life and everyday activities, as well as significant financial, social, and healthcare expenses 5,6 . RLS has been significantly associated with obesity, hypertension, diabetes and metabolic syndrome 7,8 .
According to the most recent data from the World Health Organization (WHO) 422 million individuals worldwide have been diagnosed with diabetes mellitus 9 . Diabetes mellitus currently affects 240 million people worldwide, with the figure expected to rise to 380 million by 2025, with low-and middle-income nations bearing the brunt of the burden 10 . Pakistan is now ranked 6th among countries with the highest prevalence of diabetes mellitus 11 . Pakistan is in a high-prevalence area, with 6.9 million people currently affected and anticipated projections of 11.5 million people affected by 2025 12 .
In type 2 DM diabetes-related Peripheral neuropathy is very frequent and called diabetic polyneuropathy. Routine Symptoms described by patients are tingling, uncomfortable sensation and ache in the lower extremities while walking. Diabetes-related eye ailment retinopathy, irregular and abnormal lipid quantity in the body, cardiovascular disorders, unemployed status and diabetes mellitus for more than 5 years are significantly associated with diabetic poly neuropathy 13 . When a high level of glucose in the blood and for a longer duration of time occurs, nerve ending of upper and lower extremities particularly the distal-most segments like hands and feet often experience neuropathic complications 14,15 .
Diabetes mellitus is a group of metabolic disorders in which blood glucose level increases because of abnormality in the secretion of insulin, its action, or both 15 . In type 2 diabetes mellitus, impaired glucose metabolism results in polyuria, polydipsia and physical impairment causing sleep disturbances. The association between RLS and diabetes has been reported previously 16 . This study was conducted to compare the frequencies of restless leg syndrome in diabetic patients with or without neuropathy and to compare the quality of sleep of diabetes patients with and without neuropathy.

METHODS
The comparative cross-section survey was conducted from February 2021 to June 2021 at Railway General Hospital Rawalpindi, Pakistan. After approval from the Riphah College of Rehabilitation and Allied Health Sciences' ethics review committee (Ref # Riphah/RCRS/REC/00907) and the heads of the participating institution, the sample size was calculated as 271 keeping the 90% confidence interval, 5% margin of error and response distribution as 50% with 20000 population size by using Raosoft. Patients with diagnosed diabetes were subsequently recruited with no history of malignancy and any other hereditary or systemic illness. After getting informed consent from the participants, the restless leg syndrome-Disability Index scale was used for assessing restless leg syndrome and the Pittsburg Sleep Quality Index scale for quality of sleep in all the participants. Questionnaires were explained to respondents. The subjective sleep quality, sleep latency, sleep length, habitual sleep efficiency, sleep disruptions, usage of sleeping medications, and daytime dysfunction are the seven "component" scores that are generated from the 19 individual items.
Every questionnaire has been filled by researchers themselves from every diabetic patient. One overall score is produced by adding the scores for these seven components. The mean and standard deviation were calculated using descriptive analysis. Categorical variables were expressed as proportions and percentages while continuous variables were expressed in terms of Mean±SD. A Chi-square test was used to find the association of restless leg syndrome with quality of sleep and an independent t-test was used to a comparison of the restless leg syndrome and sleep quality in diabetic patients with and without neuropathy. To compare the relationship between quality of sleep in diabetic patients with and without neuropathy one-way ANOVA was applied. For statistical analysis of the data, SPSS 21 was used was p-value less than 0.05 was considered significant.

RESULTS
A total of 271 participants with diagnosed cases of diabetes mellitus were enrolled in this study. Among them, 83 cases (30.6%) were without diabetic neuropathy and [188(69.4%)] were with diabetic neuropathy. The percentage of female participants in this study is [76% (206)] and that of the male is [24% (65)] (Figure 1). Data was tested for normality using the Shapiro-Wilk test. A parametric test has been used to compare the RLS in diabetic patients with neuropathy and without neuropathy. There is a significant relation between restless leg syndrome in diabetic patients with neuropathy (Mean±S-D=2.65±1.36) compared to diabetic patients without neuropathy (1.20±1.44) with p< 0.01 as shown in Table 1.
There was a significant relationship found between quality of sleep in diabetic patients with neuropathy (1.87±0.33) compared to the diabetic patient without neuropathy (1.69±0.46) with a statistically significant result (p<0.001) shown in Table 2.
No sleep quality was disturbed in 48 (17.71%) participants, in them, 25 participants reported no restless leg syndrome while the remaining 23 reported mild, moderate, severe and very severe RLS. Furthermore, a total of 223 (82.28%) participants reported sleep disturbance, 48 (17.7%) reported no RLS and 175 (64.5%) participants had RLS ranging from mild, moderate, severe and very severe RLS having p<0.01.

DISCUSSION
The results suggested that there was a strong relationship between RLS in the diabetic population with neuropathy. Diabetics may experience RLS and neuropathy as a result of common risk factors such as glucose intolerance, dyslipidemia, and obesity 11 . In a case-control study, RLS was found to be comorbidity in diabetics, with a prevalence of 22.4% 17 . Multiple experimental and epidemiological studies have found that poor sleep quality is associ-

PATIENTS CONSENT
Verbal informed consent was obtained from all the patients regarding their participation in the study and publication of data while maintaining confidentiality and anonymity.