Nightmares and Broken Sleep Track Psychological Distress in Dialysis Patients, Sri Lankan Study Finds

For most people, a bad dream is a fleeting nuisance that dissolves with the morning coffee. For patients tethered to dialysis machines several times a week, the night can tell a very different story. A new cross-sectional study from Sri Lanka’s National Nephrology Specialised Hospital in Polonnaruwa suggests that the content and consequences of dreams—especially nightmares and the sleep they wreck—may be a meaningful window into the psychological state of people living with chronic kidney disease. The research, published in BMC Public Health, is among the first to examine dream characteristics in a dialysis population in a low- and middle-income country, where the mental health burden of kidney disease is often overlooked entirely.

The study team, led by E. M. S. K. Edirisinghe and colleagues, recruited 422 adults receiving maintenance dialysis at the national nephrology hospital, using consecutive non-probability sampling. Participants were interviewed with a structured questionnaire that combined several well-validated instruments: the Pittsburgh Sleep Quality Index, a widely used measure of sleep across seven components ranging from latency to daytime dysfunction; the Depression Anxiety Stress Scales-21, a shortened psychological screening tool; and six selected items from the Mannheim Dream Questionnaire, supplemented by four study-specific dream items. The interview-administered format matters in this setting, where literacy and fatigue can make self-completed questionnaires unreliable.

The headline numbers are stark. Seventy-two percent of participants—304 of the 422—qualified as poor sleepers on the Pittsburgh index, with a mean global score of 9.58 out of a possible 21, well above the conventional threshold of five that signals clinically relevant sleep disturbance. The mean total DASS-21 score was 20.71 with a standard deviation of 10.34, and when the researchers split the sample into tertiles, psychological symptom burden was spread widely across the cohort rather than concentrated in a small distressed minority. For a population already coping with a life-sustaining treatment regimen, the findings paint a picture of exhaustion layered on top of illness.

But the most striking results concern dreams. Of the ten dream characteristics assessed, six showed statistically significant correlations with psychological distress. The strongest was nightmare distress—the emotional impact of bad dreams—with a Spearman correlation coefficient of 0.50. Dream-related sleep disturbance followed at 0.47, and nightmare frequency at 0.46. In epidemiological terms, correlations of this magnitude are substantial, particularly for a phenomenon as rarely measured as dreaming. The suggestion that the emotional tone of sleep might mirror the emotional burden of waking life is not new in dream science, but demonstrating it in a dialysis cohort in rural Sri Lanka adds an unexpected and clinically useful data point.

To move beyond simple correlations, the team built a multiple linear regression model, adjusting for sleep quality and socio-demographic variables and applying a Benjamini–Hochberg correction to guard against false positives across multiple comparisons. Dream-related sleep disturbance emerged as the strongest independent predictor of distress, with a standardized beta of 0.34, followed by nightmare frequency at 0.27. Male sex, longer dialysis duration, higher global Pittsburgh Sleep Quality Index scores, and unemployment were all positively associated with distress, each with betas around 0.08 to 0.10. Being married was inversely associated, with a beta of minus 0.09, hinting at a protective effect of partnership. The model as a whole explained 43 percent of the variance in distress scores—adjusted R-squared of 0.43—which is respectable for psychological research in a medical population.

The direction of these associations invites careful interpretation, and the authors are appropriately cautious. Because the study is cross-sectional, it cannot establish whether distressing dreams drive psychological distress, whether distress breeds nightmares, or whether both flow from a common source such as chronic inflammation, uremia, or the sheer stress of dialysis dependence. Nor can the design determine whether dialysis patients dream more badly than the general population, since there was no comparison group. What the study does establish is that dream-related sleep disturbance carries information about distress that is not fully redundant with measured sleep quality or demographic risk factors—a non-trivial finding for anyone designing screening protocols.

The mechanistic plausibility is worth unpacking. Sleep in dialysis patients is already fragmented by physical discomfort, restless legs, pruritus, and the metabolic derangements of kidney failure. Rapid eye movement sleep, the stage in which vivid dreams and nightmares predominantly occur, is sensitive to stress hormones and to sleep fragmentation itself. A patient whose night is repeatedly interrupted may experience rebound REM periods punctuated by intense, emotionally charged dreams, which in turn heighten nocturnal arousal and further degrade sleep. This feedback loop—poor sleep breeding disturbing dreams breeding worse sleep—is a recognized model in insomnia research, and cognitive-behavioral therapy for insomnia is one established intervention that targets it. Whether such approaches work in dialysis populations remains to be tested.

The Sri Lankan setting gives the findings particular public health weight. Chronic kidney disease, including chronic kidney disease of undetermined aetiology, has reached epidemic proportions in agricultural regions of the country, and Polonnaruwa sits at the heart of the affected zone. In low- and middle-income countries, nephrology services are typically stretched to deliver life-sustaining dialysis, leaving psychological care and sleep medicine far down the priority list. The authors argue that sleep and psychological assessment should remain clinical priorities in dialysis units, and that a targeted question about recurrent distressing dreams—a query that costs nothing to ask—may help identify symptomatic patients who would otherwise go unnoticed.

The demographic predictors also deserve attention. The cohort was 67.1 percent male, with a mean age of 54.6 years, and male sex independently predicted higher distress even after adjustment. Longer time on dialysis and unemployment both added to the burden, consistent with the idea that the psychological toll of kidney disease accumulates with treatment duration and is compounded by lost livelihood. The inverse association with marriage echoes a long literature on social support and mental health, suggesting that household relationships may buffer some of the emotional cost of chronic illness in this cultural context.

For now, the study’s practical takeaway is modest but actionable: clinicians caring for dialysis patients should ask about sleep and about dreams, not as an afterthought but as part of routine assessment. A patient who reports nightmares that wake them and bleed into their daytime functioning may be flagging psychological distress that a standard medical review would miss. The authors are explicit that their findings warrant further evaluation rather than immediate causal claims, and that the absence of a comparison group means no one should conclude that dialysis patients are uniquely plagued by nightmares. Still, in a field where the inner experience of patients is so often reduced to lab values and clearance rates, a study that takes dreams seriously—and finds that they correlate with real, measurable suffering—represents a genuinely fresh angle on an old problem. The next step will be longitudinal work that can disentangle whether healing sleep, or healing dreams, helps heal the mind.

Subject of Research: Sleep quality, dream characteristics, and psychological distress in dialysis patients with chronic kidney disease

Article Title: Dreaming, sleep quality, and psychological distress among patients with chronic kidney disease at a national nephrology hospital in Sri Lanka: a descriptive cross-sectional study

Article References: Edirisinghe, E. M. S. K., Wimalasiri, A. J. W. A. N., Sirithunga, S. S., Ekanayake, A. G. W. K., Edirisinghe, D. A. S., Rathnakumari, K. N., & Perera, A. C. H. (2026). Dreaming, sleep quality, and psychological distress among patients with chronic kidney disease at a national nephrology hospital in Sri Lanka: a descriptive cross-sectional study. BMC Public Health. https://doi.org/10.1186/s12889-026-29765-0

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29765-0

Keywords: chronic kidney disease, dialysis, sleep quality, nightmares, psychological distress, dreaming, Pittsburgh Sleep Quality Index, DASS-21, Sri Lanka, cross-sectional study, public health, sleep