Does smoking increase blood pressure risk? Urine tests reveal the answer

Most people know smoking hurts the heart. The knotty question has been whether it pushes up blood pressure on its own or just travels with other risks.

A new analysis says yes, the link is real. It says the signal gets clearer when researchers check urine for chemicals from tobacco, rather than relying only on what people say.

Smoking impacts blood pressure

The study was led by Dr. Setor K. Kunutsor at the University of Manitoba (UM), working with collaborators in the Netherlands.

The team tracked 3,296 adults with no history of hypertension, a condition where blood pressure stays higher than normal.

The researchers collected self-reported smoking data and confirmed it with a urine test measuring cotinine – a byproduct of nicotine breakdown. They then tracked participants for a median of 7.2 years to see who developed high blood pressure.

The participants were classified as never, former, light current, or heavy current smokers by both self-report and the cotinine ranges in urine.

The experts estimated how much each smoking category changed the odds of new high blood pressure compared with people who had never smoked.

Why a urine test matters

Public health labs have long relied on cotinine in blood or urine to confirm recent nicotine exposure. It sticks around longer than nicotine, which makes it a practical lab marker.

Urine testing can also spot exposure to secondhand smoke – tobacco smoke breathed in from other people’s cigarettes – that a patient may not think to mention. That extra layer of measurement helps clinicians and researchers sort out under-reporting.

CDC scientists describe serum cotinine as “an indicator of recent nicotine exposure,” wrote the authors of a federal MMWR analysis. The same approach applies to urine in clinical studies and routine care.

Smoking raises blood pressure

In this PREVEND (Prevention of Renal and Vascular End-Stage Disease) cohort, 832 people developed high blood pressure during follow-up.

After accounting for age, sex, and other factors, people with higher nicotine exposure were more likely to develop high blood pressure.

The risk was about 30 percent higher for light smokers and 60 percent higher for heavy smokers, based on urine cotinine levels.

The message stayed consistent across both ways of measuring smoking. Heavier exposure meant higher risk.

“Light and heavy current smoking, as assessed by self-reports and urine cotinine, are each associated with an increased risk of hypertension,” wrote Kunutsor.

Secondhand smoke and hidden risks

Urine tests do more than confirm active smoking. They can reveal passive exposure – the inhalation of smoke from others – that quietly adds cardiovascular strain.

One large study in northwest China found that adults exposed to secondhand smoke had a higher likelihood of hypertension, with a clear time and frequency dose-response pattern. Added passive exposure on top of active smoking pushed risk even higher.

This matters in homes, workplaces, and social spaces where smoke lingers. A brief conversation rarely captures those details, but cotinine often does.

Smoking linked to high blood pressure

The study focused on new cases of high blood pressure emerging during follow-up. That let the researchers connect smoking patterns at baseline with later outcomes.

They also compared the two exposure measures side by side. Self-reports lined up with cotinine in broad strokes, yet the lab test made the association with hypertension easier to see.

Interpreting former smokers

A twist surfaced when cotinine labeled many people as never smokers even though they called themselves former smokers. That is expected, since cotinine only reflects recent exposure.

Former smokers can still carry extra cardiometabolic risk, meaning higher odds of heart or metabolic disease, compared with never smokers.

Evidence from a large national cohort shows that ex-smokers with heavier lifetime exposure can take decades for their cardiovascular risk to fall to the level of never smokers.

This is why a good history still matters. A urine test clarifies recent exposure, while the story of total pack years – the number of packs smoked per day multiplied by years of smoking – fills in the long arc.

What this means in the clinic

Doctors can use a quick urine cotinine test, a lab check for nicotine breakdown products, to verify smoking status, uncover secondhand exposure, and guide specific counseling. Seeing an objective number often opens the door to a more candid talk.

The numbers in this study suggest that even light daily smoking carries measurable risk for high blood pressure. That supports early cessation and smoke-free environments as part of routine blood pressure care.

For patients who already quit, clinicians can weigh lifetime tobacco burden when judging cardiovascular risk. That helps set the intensity of prevention plans.

Where tech could help next

Wearable sensors, small devices that track biological data, are being tested to detect smoking episodes in daily life.

A 2024 scoping review mapped wrist motion trackers, thermal badges, and environmental monitors that could capture exposure continuously.

These tools are not ready to replace lab tests or careful interviews. They could, however, strengthen research on tobacco exposure and make prevention more timely.

High blood pressure often creeps up without symptoms. Smoking, even at low levels, raises the chances it will appear sooner.

The study is published in the Journal of Human Hypertension.

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