High blood pressure, also known as hypertension, is a widespread health issue affecting over a third of Australian adults aged 18 and above. If left untreated, it can lead to severe health problems like heart disease and stroke.
To manage hypertension, doctors often prescribe medications such as hydrochlorothiazide, which is one of the most commonly used drugs in Australia.
However, a recent study from UNSW Sydney has uncovered a concerning link between hydrochlorothiazide and an increased risk of skin cancer in older adults. The researchers found that this popular blood pressure medication might raise the chances of developing skin cancers, including lip cancer and malignant melanoma.
This connection is believed to be due to the way hydrochlorothiazide makes the skin more sensitive to sunlight, increasing the risk of sun damage.
The study was based on data collected by the Department of Veterans’ Affairs (DVA) in New South Wales. The research included information about cancer cases, hospital visits, and medication use among healthcare cardholders aged 65 and older.
The data covered a period from 2004 to 2015, providing a long-term view of health outcomes for people using this medication.
To understand the link, the researchers compared the medical records of people diagnosed with skin cancers—45 cases of lip cancer and 659 cases of malignant melanoma—with a control group of 13,300 individuals who did not have these cancers.
They found that those who took hydrochlorothiazide had a noticeably higher risk of developing both malignant melanoma and squamous cell lip cancer.
Even more concerning was the discovery that the risk of lip cancer grew with long-term use of the medication. In simple terms, the longer a person took hydrochlorothiazide, the greater their risk of developing lip cancer.
This raises questions about the safety of long-term use of the drug, particularly for older adults who are more likely to be prescribed it for blood pressure control.
Despite these alarming findings, the researchers strongly advise against stopping hydrochlorothiazide without medical guidance. High blood pressure needs to be carefully managed, and suddenly discontinuing the medication can be dangerous.
Dr. Benjamin Daniels, who led the study, emphasized the importance of talking to a doctor before making any changes to medication routines.
The study’s authors suggest that healthcare providers should be more aware of this skin cancer risk and take extra steps to protect patients. This could include regular skin checks, especially for those who have been on hydrochlorothiazide for many years.
Doctors might also encourage patients to adopt good sun protection habits, such as wearing sunscreen, protective clothing, and avoiding direct sunlight during peak hours.
In response to the study’s findings, the prescribing information for hydrochlorothiazide has been updated to include the potential risk of skin cancer. This change aims to make healthcare providers more aware of the risks and encourage them to take necessary precautions when prescribing the drug.
The findings from UNSW Sydney support earlier international studies that also found a connection between hydrochlorothiazide and skin cancer. This adds to the growing awareness that medications for managing chronic conditions can sometimes have unexpected side effects.
For patients, the study serves as a reminder to be mindful of sun safety, particularly if they are taking medications that make their skin more sensitive to UV rays. Simple steps like applying sunscreen, wearing a hat, and seeking shade during sunny days can make a big difference.
Dr. Daniels and his team published their research in the journal Basic & Clinical Pharmacology & Toxicology. The study brings new insights into the risks linked with one of the most commonly prescribed blood pressure medications.
It highlights the need for a balanced approach to treating chronic conditions, considering both the benefits and potential risks of long-term medication use.
While managing high blood pressure remains crucial, this study shows the importance of looking at the bigger picture—ensuring that the treatment for one condition does not unintentionally increase the risk of another.
For older adults, especially those who have been taking hydrochlorothiazide for many years, regular skin checks and sun safety measures are simple yet effective ways to reduce this added risk.
If you care about high blood pressure, please read studies about unhealthy habits that may increase high blood pressure risk, and drinking green tea could help lower blood pressure.
For more information about high blood pressure, please see recent studies about what to eat or to avoid for high blood pressure, and 12 foods that lower blood pressure.
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