| Abstract|| |
The purpose of this study was to determine the quality of life and sleep of chronic hemodialysis (HD) patients. Quality of sleep was measured using the Pittsburgh Sleep Quality Index (PSQI) and quality of life (QoL) was measured using the Medical Outcomes Study 36-item Short Form (SF-36) in 115 HD patients. One hundred (87%) patients were "poor sleepers" (global PSQI ≥5). The SF-36 mental component summary and physical component summary (PCS) scores were higher than 50 only in 43% and 32% of the subjects, respectively. No significant differences were found in QoL and sleep according to the patient's gender, presence of diabetes and time on HD. Correlation between total SF-36 score and global PSQI was statistically significant (r = -0.227, P <0.05). Poor sleep is common in dialysis patients and is associated with lower QoL, especially with mental health component of life quality.
|How to cite this article:|
Edalat-Nejad M, Qlich-Khani M. Quality of life and sleep in hemodialysis patients. Saudi J Kidney Dis Transpl 2013;24:514-8
| Introduction|| |
Although there have been improvements in end-stage renal disease (ESRD) treatment, patients continue to have significant problems with their quality of life (QoL). ESRD and hemodialysis (HD) have been associated with reduced QoL compared with the general population,  and measures of QoL in ESRD have been associated with increased frequency of hospitalization and mortality rates. ,,,
Also, sleep complaints are common in HD patients, and include delayed sleep onset, frequent awakening, restlessness and daytime sleepiness. ,,,,,,
We aimed from our study to determine the prevalence of "poor sleep" in HD patients and to examine the association between quality of sleep and QoL.
| Patients and Methods|| |
This cross-sectional study was performed in the HD unit of the medical center of Vali-Asr, Arak, Iran. It was approved by the Arak Medical Sciences University Research Ethics Review Committee (No. 88-76-4) and informed consents were obtained from all participants. All patients received daytime dialysis, and the total hours per week varied from 8 h to 13.5 h. The inclusion criteria were as follows: Patients should have been receiving maintenance HD >3 months; age >18 years and provided informed consent.
The personal information form (PIF) was developed by the researchers and included questions about the patients' age, gender, educational level, occupation and duration of HD treatment.
Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI).  This 19-question questionnaire measures the sleep quality of the previous month. From the answers, seven components (each scored from 0 to 3) were calculated: Subjective sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbance, use of sleep medications and daytime dysfunction. From the sum of the scores of the seven components, the global PSQI score was calculated (0-21). A patient with a global PSQI score 5 was considered as a bad sleeper and a patient with a value of <5 was considered as a good sleeper. The patients completed the questionnaire by themselves or with the assistance of research nurses at the time when the HD was performed.
The SF-36, one of the most commonly used health status questionnaires, was developed as a measure of function and well-being in the Medical Outcomes Study. It comprised 36 items evaluating eight dimensions of health: Physical functioning, role limitations due to physical problems, physical pain, general health perceptions, vitality, social functioning, role limitations due to emotional problems and mental health. Each dimension is scored on a 0 to 100 scale, with lower scores corresponding with more significant dysfunction.
The SF-36 is divided into two domains: Physical health (PCS) and mental health (MCS). The PCS and MCS scores are standardized to a mean of 50, with scores above and below 50 indicating above and below average functioning, respectively. Global SF, PCS and MCS scores can all vary between 0 and 100. A high score indicates a better QoL. We screened the patients' QoL in all eight dimensions of health and global SF, PCS and MCS.
After obtaining the informed consents and excluding patients with the major barriers for filling QOL and sleep evaluator questionnaires (such as dementia or psychotic disorder, as diagnosed by researcher) and ruling out the presence of malignancy, active infection, uncontrolled heart failure and acute medical or surgical condition that required hospitalization or operation within the prior month, we enrolled 115 patients for assessment of QoL and sleep. We gathered medical and demographic data by reviewing of patients medical records and measured QoL and sleep scores from patients' answers to questionnaires of the PSQI and the Medical Outcomes Study 36-item Short Form (SF-36).
| Statistical Analysis|| |
The Statistical Package for Social Sciences (SPSS) version 15.0 was used for data analysis in the study. Pearson correlation analysis was used to determine relationships between QoL and sleep quality, QoL and age, QoL and duration of HD, sleep quality and age, and sleep quality and duration of HD. The t-test and analysis of variance were used in the evaluation of QoL and sleep quality according to demographic characteristics. P-value <0.05 was considered significant.
| Results|| |
Of the 155 patients available to enter the study, 40 did not meet inclusion criteria or did not complete the PSQI and the SF-36 questionnaires. One hundred and fifteen patients were included in the analysis. The age range of the patients was 19-87 years, with a mean age of 63 ± 15 years. Sixty-five (55.7%) patients were male and five had failed renal allografts. The causes of renal disease were: vascular/ hypertension (43), diabetic nephropathy (34), glomerulonephritis (eight), polycystic kidney disease (seven), urological problem (four) and unknown (19). The majority of patients attended HD for 4 h three times weekly.
The majority of patients were illiterate (52.2%), and only 7.8% had high school or graduate study. In this study, less than 30% reported the perception that their income was sufficient.
The mean (SD) global and component PSQI scores for the study population are shown in [Table 1]. The global PSQI score ranged from 0 to 21, and 100 (87%)patients were "poor sleepers" (global PSQI ≥5). For patients who recorded the cause of sleep disturbance, 42 described severe restless legs and 28 described trouble breathing. No significant differences were found between PSQI scores according to patients' gender, age and time on HD.
|Table 1: Quality of sleep in the study population according to the Pittsburgh Sleep Quality Index (PSQI).|
Click here to view
The mean (±SD) scores for the SF-36 MCS, PCS and HRQoL domains are shown in [Table 2]. The MCS ranged from 19.1 to 68.7 (44.0 ± 15.9), while the PCS ranged from 12.8 to 62.0 (41.0 ± 13.1). The total SF-36 score ranged from 14 to 91 (44.7 ± 14.2). Only 45 patients (39%) had a total SF-36 score more than 50. Prevalence of PCS and MCS scores higher than 50 based on self-reported items were 32% and 43%, respectively.
The effects of kidney disease on the QoL were assessed and their results are shown in [Table 3]. The main adverse effect of renal failure and HD is reflected on occupation and income.
As shown by the analysis of data, there was a significant relationship between age and QoL in our study (P <0.05). However, there was no correlation between QoL and quality sleep scores and time on dialysis. Furthermore, we did not find differences of PSQI and SF-36 scores and between males and females and between diabetics and non-diabetics.
There was a negative relationship between the quality of sleep and the MCS scores (r = -0.222; P <0.01), and the global SF-36 (r = -0.227; P >0.05) show that as the quality of sleep worsened, the QoL decreased. Unlike the MCS scores, there was no correlation between the PCS and the global PSQI (r = -0.159; P = 0.090). In addition, we assessed the correlation between the PCS components and the global PSQI, and noticed a correlation between physical functioning (r = 0.196; P <0.05) and body pain (r = -0.192; P <0.05) in a positive and a negative way, respectively.
| Discussion|| |
In the present cross-sectional study, quality of sleep and QoL were measured using validated questionnaires. The PSQI and SF-36 evaluated quality of sleep and QoL during the preceding 4-week period.
The prevalence of poor sleep in the present study was 87%, comparable with the 70-89% prevalence of sleep-wake complaints in dialysis patients reported in previous studies. ,,,,, Also, the prevalence of low QoL based on self-reported total SF-36 score measurement was 60%, which is much better than most previous reports. , Prevalence of PCS and MCS scores higher than 50 based on self- reported items were 32% and 43%, respectively. These findings suggest that our patients had better perception of mental health compared with physical health. There was a strong association between quality of sleep and mental QoL, especially for subjective sleep quality and sleep efficiency. However, we did not find a significant correlation between quality of sleep and physical QoL. In the present study, only mental QoL was associated with sleep efficiency, subjective sleep quality and use of sleep medications. Our findings were compatible with those of Sathuik et al  ; however, the majority of studies have shown a strong association between quality of sleep and PCS of SF-36 scores, seperately ,, or in conjunction with components of mental health. , The best evidence that ESRD can directly influence quality of sleep, which in turn results in reduced QoL, comes from studies of obstructive sleep apnea (OSA) in dialysis patients; OSA is common in dialysis patients. ,, In the present study, 28 (24%) patients described trouble breathing and 42 (36%) described severe restless legs.
In our study, quality of sleep and QoL were not associated with time on HD in the bivariate analysis. These findings are consistent with other studies. 
No statistically significant differences in patients' sleep quality scores were found according to their age. However, there were differences in patients' mental health component of QoL based on their age. These results were similar to the results from previous studies. ,
Furthermore, we noted no statistically significant differences in patients' QoL and sleep quality scores between diabetic and non-diabetic patients. These results were different from the findings of Nazmiye et al.  They showed a significant association between the sleep quality and presence of diabetes mellitus. Sorensen et al  showed a correlation between diabetes and low PSC scores, but not MSC scores. We assumed that this difference comes from excluding diabetics with severe comorbidity such as cardiovascular problems and neuropathy from our study population.
Some studies have reported a negative correlation between QoL and female gender, ,, but we did not detect any statistical difference in QoL or sleep quality according to gender. In this study, more than half of the patients were female.
There were several limitations in our study. First of all, because of the cross-sectional design, it is not possible to establish a cause and effect relationship in the examined associations. Second, in the absence of polysomnographic data, it is not possible to ascertain the exact causes of insomnia and sleep disturbance. Also, subjective reports of sleep quality do not have a single criterion standard.
In conclusion, the results of this study suggest that "poor sleep" and low QoL are common in dialysis patients.
| Acknowledgment|| |
The authors would like to thank the staff and patients of the Vali-Asr HD center.
| References|| |
|1.||Fukuhara S, Lopes AA, Bragg-Gresham JL, et al. Health-related quality of life among dialysis patients on three continents: The dialysis outcomes and practice patterns study. Kidney Int 2003;64:1903-10. |
|2.||Mapes D, Lopes A, Satayathum S. Health-related quality of life as a predictor of mortality and hospitalization: The dialysis outcomes and practice patterns study (DOPPS). Kidney Int 2003;64:339-49. |
|3.||DeOreo PB. Hemodialysis patient-assessed functional health status predicts continued survival, hospitalization, and dialysis-attendance compliance. Am J Kidney Dis 1997;30: 204-12. |
|4.||Kalantar-Zadeh K, Kopple JD, Block G, Humphreys MH. Association among SF36 quality of life measures and nutrition, hospitalization, and mortality in hemodialysis. J Am Soc Nephrol 2001;12:2797-806. |
|5.||Lowrie EG, Curtin RB, LePain N, Schatell D. Medical Outcomes Study Short Form-36: A consistent and powerful predictor of morbidity and mortality in dialysis patients. Am J Kidney Dis 2003;41:1286-92. |
|6.||Holley JL, Nespor S, Rault R. A comparison of reported sleep disorders in patients on chronic hemodialysis and continuous peritoneal dialysis. Am J Kidney Dis 1992;19:156-61. |
|7.||Walker S, Fine A, Kryger MH. Sleep complaints are common in a dialysis unit. Am J Kidney Dis 1995;26:751-6. |
|8.||Williams SW, Tell GS, Zheng B, Shumaker S, Rocco MV, Sevick MA. Correlates of sleep behavior among hemodialysis patients. Am J Nephrol 2002;22:18-28. |
|9.||Hanly PJ, Pierratos A. Improvement of sleep apnea in patients with chronic renal failure who undergo nocturnal hemodialysis. N Engl J Med 2001;344:102-7. |
|10.||Kimmel PL, Miller G, Mendelson WB. Sleep apnea syndrome in chronic renal disease. Am J Med 1989;86:308-14. |
|11.||Benz RL, Pressman MR, Hovick ET, Peterson DD. Potential novel predictors of mortality in end-stage renal disease patients with sleep disorders. Am J Kidney Dis 2000;35:1052-60. |
|12.||McClellan WM, Anson C, Birkeli K, Tuttle E. Functional status and quality of life: Predictors of early mortality among patients entering treatment for end stage renal disease. J Clin Epidemiol 1991;44:83-9. |
|13.||Buysse DJ, Reynolds CF, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: A new instrument for psychiatric practice and research. Psychiatry Res 1989;28:193-213. |
|14.||Iliescu E, Coo H, McMurray MH, et al. Quality of sleep and health-related quality of life in hemodialysis patients. Nephrol Dial Transplant 2003;18:126-32. |
|15.||Unruh ML, Buysse DJ , Amanda Dew M, et al. Sleep quality and its correlates in the first year of dialysis. Clin J Am Soc Nephrol 2006; 1:802-10. |
|16.||Eryavuz N, Yuksel S, Acarturk G, et al. Comparison of sleep quality between hemodialysis and peritoneal dialysis patients. Int Urol Nephrol 2008;40:785-91. |
|17.||Chiu YL, Chuang YF, Fang KC, et al. Higher systemic inflammation is associated with poorer sleep quality in stable hemodialysis patients. Nephrol Dial Transplant 2009;24: 247-51. |
|18.||Sabbagh R, Iqbal S, Vasilevsky M, Barré P. Correlation between physical functioning and sleep disturbances in hemodialysis patients. Hemodial Int 2008;12:20-4. |
|19.||Pai MF, Hsu SP, Yang SY, Ho TI, Lai CF, Peng YS. Sleep disturbance in chronic hemodialysis patients: The impact of depression and anemia. Ren Fail 2007;29:673-7. |
|20.||Tel H. Determining quality of life and sleep in hemodialysis patients. Dial Transplant 2009; 38:210-15. |
|21.||Sathvik BS, Parthasarathi G, Narahari MG, Gurudev KC. An assessment of the quality of life in hemodialysis patients using the WHOQOL-BREF questionnaire. Indian J Nephrol 2008;18:141-9. |
|22.||Sorensen VR, Mathiesen ER, Watt T, Bjorner JB, Andersen MV, Feldt-Rasmussen B. Diabetic patients treated with dialysis: complications and quality of life. Diabetelogia 2007;50:2254-62. |
Assistant Professor of Nephrology, Arak Medical Sciences University, Arak
[Table 1], [Table 2], [Table 3]