Does Kidney Disease Affect Body Temperature?

Kidney disease, particularly in its advanced stages, tends to lower baseline body temperature and disrupt the body’s ability to regulate heat. Many people with chronic kidney disease run cooler than the commonly cited 98.6°F, and their bodies often struggle to mount a normal fever when fighting infection. The reasons trace back to how waste products, metabolic shifts, and even dialysis treatment itself interfere with the internal thermostat, with consequences that go well beyond simply feeling chilly.

Why Kidney Disease Lowers Resting Body Temperature

As kidney function declines, waste products that the kidneys would normally filter out accumulate in the blood. This buildup, known as uremia, appears to directly interfere with the brain’s temperature-regulating center in the hypothalamus. Experimental and clinical evidence suggests that uremia dampens the hypothalamic responses that ordinarily keep the body at a stable temperature. On top of that, uremic toxins seem to act as internal cooling agents: they promote blood vessel dilation near the skin’s surface (which radiates heat outward) and suppress shivering, one of the body’s main mechanisms for generating warmth when it gets too cold.¹

At the cellular level, the picture gets clearer. The high concentration of waste solutes like urea disrupts how cells use oxygen and how mitochondria produce energy. When mitochondrial function falters, the body generates less heat as a byproduct of metabolism. Think of it this way: a healthy body is like a furnace that constantly burns fuel and throws off warmth. Uremia is like partially clogging the furnace’s air intake. The fire still burns, but it produces less heat.²

How common is a measurably low temperature? In one study of 128 hemodialysis patients across two dialysis units, about one in five had an average baseline temperature below 36°C (96.8°F). Meanwhile, a separate analysis found that hemodialysis patients had an estimated baseline temperature around 98.0°F, statistically lower than the traditional 98.6°F benchmark.³

The Hidden Danger of a Blunted Fever

A lower resting temperature might sound minor, but it creates a serious clinical problem. Because people with advanced kidney disease start from a cooler baseline, a temperature that looks “normal” on a thermometer might actually represent a significant fever for them. And the problem is compounded by the fact that their immune systems often cannot generate as strong a febrile response in the first place. Uremic patients frequently show a blunted fever when fighting infection, meaning their temperature rises less than expected even when bacteria are in their bloodstream.⁴

The clinical stakes here are real. In a study comparing hemodialysis patients and non-dialysis patients who all had confirmed bloodstream infections, about 54% of the hemodialysis patients did not meet the standard fever threshold of 100.4°F when they arrived at the emergency department. Among the non-dialysis patients with the same types of infections, the number without detectable fever was even higher at 82%, but for a different reason: the dialysis patients’ temperatures were actually more elevated relative to their own baselines. When researchers compared each hemodialysis patient’s emergency department temperature to their own personal baseline, the jump was clear. Their average triage temperature was about 100.6°F, well above their usual 98.0°F. But because 100.6°F doesn’t always trigger alarm bells in a busy emergency room, these infections risk being missed or treated with less urgency.³

If you or a family member has kidney disease, this is one of the most practical takeaways: know your normal temperature. A reading of 99.5°F might look unremarkable to an ER nurse consulting a standard reference chart, but if your usual temperature sits around 97.5°F, that two-degree jump could signal a serious infection. Some nephrologists recommend tracking baseline temperatures over time so that any deviation is immediately recognizable.

How Dialysis Itself Shifts Body Temperature

Dialysis adds another layer of complexity. During hemodialysis, blood flows out of the body and through a machine before being returned. The temperature of the fluid used in the machine, called the dialysate, directly affects the temperature of the blood that comes back. The blood returns to the patient in thermal balance with the dialysate, which means the machine is essentially adding or removing heat with every pass.⁵

What catches many patients off guard is that even dialysate set to match their measured body temperature can cause their core temperature to rise. That happens because the body’s internal core is slightly warmer than the sites where temperature is typically measured, like the mouth or armpit. So dialysate at 37°C might feel “neutral” on paper, but it is actually pumping extra heat into the body. In one study, patients on standard-temperature dialysis (37.5°C) saw their core temperature climb from about 36.7°C to 37.2°C over the course of a session, despite actually losing a small amount of heat to the machine. The dialysis procedure itself appeared to independently push core temperature upward.⁶

This rise in core temperature triggers blood vessels near the skin to dilate, which can cause blood pressure to drop. For patients already at risk of low blood pressure during dialysis, that temperature-driven drop can cause dizziness, nausea, cramping, or fainting. It is one of the most common reasons dialysis sessions are cut short or patients feel terrible afterward.

Cooling the Dialysate to Improve Tolerance

Clinicians figured out decades ago that lowering the dialysate temperature could counteract the blood pressure drops that plague many dialysis patients. The logic is straightforward: cooler blood returning to the body triggers the blood vessels to constrict instead of dilate, helping to maintain blood pressure. This technique, known as cool dialysis, was originally developed specifically to trigger that vascular constriction response.⁷

Studies have confirmed that cooler dialysate (around 35.5°C instead of the standard 37.5°C) keeps core temperature stable rather than letting it climb. In those studies, patients on cool dialysis maintained a steady core temperature throughout the session, while also losing substantially more heat to the machine. Their blood pressure held steadier because the body compensated with greater blood vessel resistance rather than letting vessels relax.⁶ In patients prone to blood pressure drops during dialysis, cool dialysis produced significantly greater increases in vascular resistance, helping to maintain stable mean arterial pressure even as fluid was removed.⁸

The tradeoff is comfort. Cool dialysis can make patients feel cold, cause shivering, and add to an already unpleasant experience. One study found that warming gowns worn during catheter-based hemodialysis significantly reduced shivering and raised body temperature in the intervention group, from an average of 36.36°C to 36.84°C, while the control group showed no change.⁹ This suggests that external warming strategies can offset some of the discomfort without undermining the cardiovascular benefits of cooler dialysate.

Continuous Renal Replacement Therapy in Critical Care

Outside of regular outpatient dialysis, critically ill patients in intensive care units sometimes receive a slower, continuous form of blood filtration called continuous renal replacement therapy (CRRT). Because blood circulates through tubing outside the body for hours or even days, heat loss to the environment is a constant concern. A retrospective study of ICU patients on CRRT found that body temperature dropped by a median of 0.6°C in the twelve hours after CRRT was started. When the treatment was stopped, temperature rebounded by 0.6°C in the following twelve hours. Over the full course of treatment, there was a net rise of about 0.3°C from start to finish, but the pattern of cooling at initiation and warming at cessation was consistent.¹⁰

For ICU clinicians, this creates a monitoring challenge. If a patient’s fever drops right when CRRT starts, is the infection improving or is the machine simply pulling heat out of the body? Distinguishing between the two matters enormously when deciding whether to escalate or scale back antibiotics.

What It Actually Feels Like to Be Cold All the Time

The temperature changes associated with kidney disease are not just something that shows up on lab charts. They profoundly affect quality of life. A qualitative study of in-center hemodialysis patients found that many described feeling cold as a new and persistent symptom that appeared after their kidney disease diagnosis. Participants reported cold hands and feet, needing more layers of clothing, keeping their homes at 24°C to 25°C (about 75°F to 77°F), and sometimes turning on the heating even during summer months. The sensation worsened progressively over time, and autumn and winter became genuinely difficult periods. Some patients described sitting next to a heated radiator in a sweater and still not feeling warm enough.¹¹

This chronic cold sensation is often dismissed as a minor complaint compared to the other burdens of kidney disease, but it affects sleep, mood, social activity, and willingness to leave the house. It also complicates dialysis, where patients arrive already feeling cold and then may have cool fluid circulated through their blood for several hours. Understanding that feeling cold is a recognized physiological consequence of kidney disease, not a personality quirk or something patients should just “put up with,” can help both patients and caregivers take it seriously as a symptom worth managing.

The Thyroid Connection

Kidney disease does not just affect temperature regulation directly. It also disrupts the thyroid hormone system, which plays a central role in setting the body’s metabolic rate and, by extension, how much heat it produces. Chronic kidney disease is known to alter the pituitary-thyroid axis and the way thyroid hormones are processed in the body. The most common abnormality is low levels of T3, the active form of thyroid hormone, followed by a mild underactive thyroid state.¹²

Low T3 on its own can produce cold intolerance, fatigue, and sluggish metabolism, symptoms that overlap heavily with the direct effects of uremia. This overlap makes it easy to attribute everything to “just being on dialysis” when some of the problem is a treatable thyroid issue. If you have kidney disease and persistent cold intolerance, asking your doctor to check your thyroid levels is reasonable. Not every case warrants treatment, since low T3 in kidney disease sometimes reflects an adaptive response to illness rather than true thyroid failure. But the distinction matters, because when thyroid supplementation is appropriate, it can improve both energy levels and the sensation of being perpetually cold.

Resting energy expenditure in kidney disease is shaped by multiple overlapping factors, including how much kidney function remains, how much inflammation is present, what other conditions exist, and what medications are in play. The net effect varies from person to person, but the general trend is that the body’s metabolic “furnace” does not run at full capacity, producing less baseline heat than a healthy body would.¹³

Medications That Compound the Problem

Many people with kidney disease take medications for related conditions like high blood pressure or heart disease. Some of these medications have their own effects on temperature regulation. Beta-blockers, for instance, can reduce the heart’s output and limit the body’s ability to increase blood flow to the skin, which is one of the main ways the body dumps excess heat during hot weather. ACE inhibitors can alter kidney function during heat exposure. Even aspirin, commonly used in people with cardiovascular risk, affects the body’s heat-loss pathways.¹⁴

This creates a somewhat paradoxical situation. On most days, kidney disease patients feel too cold. But during heat waves or in hot environments, those same patients may be unable to shed heat effectively, putting them at risk for heat-related illness. The combination of impaired sweating (which can accompany kidney disease), medications that limit skin blood flow, and reduced kidney capacity to handle the fluid shifts that come with sweating makes extreme heat genuinely dangerous. This is an underappreciated risk, especially as heat waves become more frequent.

Peritoneal Dialysis and Temperature

Not everyone on dialysis uses a machine that pumps blood through external tubing. Peritoneal dialysis works by filling the abdominal cavity with fluid and using the body’s own peritoneal membrane as a filter. Because the dialysate sits inside the body rather than circulating through an external machine, you might expect less temperature disruption. The evidence suggests this is roughly the case. A randomized trial comparing two different dialysate temperatures in peritoneal dialysis patients found that body temperature remained comparable between the groups across different time points during treatment.¹⁵

That said, peritoneal dialysis patients are not immune to the baseline temperature effects of kidney disease itself. They still have uremia, still may have thyroid disruption, and still take the same classes of medications. What they avoid is the additional temperature stress of having blood circulated outside the body. For patients who tolerate hemodialysis poorly because of temperature-related side effects, peritoneal dialysis is sometimes worth discussing as an alternative, though the decision involves many factors beyond temperature alone.

Rare Genetic Overlap Between Sweating and Kidney Function

There is an unusual genetic condition that connects kidney damage and the inability to sweat. Researchers identified families carrying a rare mutation in the CLDN10B gene, which codes for a protein involved in forming tight junctions between cells. People with two copies of this mutation cannot sweat at all, experience severe heat intolerance, and develop mild kidney failure. The same protein is expressed in both sweat glands and kidney tubules, and the mutation disrupts both.¹⁶

This condition is extremely rare and is not the mechanism behind the temperature problems that most kidney disease patients experience. But it illustrates something interesting about the relationship between kidneys and thermoregulation: the two systems share molecular machinery. The kidneys are not just passive bystanders in temperature control. They participate in the fluid and electrolyte management that underpins how the body handles heat, and disruption at a deep enough biological level can break both systems at once.