Hypertension is often labelled as ‘the silent killer’, because it usually causes no symptoms until it reaches a life-threatening stage. Seafarers may be prone to hypertension due to the nature of their work, diet onboard, physical inactivity, alcohol and tobacco use, and a diet high in sodium usually from processed and fatty foods.

Symptoms of hypertensive crisis

In the case of hypertensive crisis, a situation in which the blood pressure quickly rises and remains to 180/120 mm Hg or higher. If pressure does not fall in to normal figures, then medical assistance is to be provided immediately. The consequences of uncontrolled blood pressure in this range can be severe and include:

  1. Stroke
  2. Loss of consciousness
  3. Memory loss
  4. Heart attack
  5. Damage to the eyes and kidneys
  6. Loss of kidney function
  7. Aortic dissection
  8. Angina (unstable chest pain)
  9. Pulmonary edema (fluid backup in the lungs)
  10. Eclampsia

A variety of symptoms may be indirectly related to, but are not always caused by, high blood pressure, such as:

  • Blood spots in the eyes: Blood spots in the eyes (subconjunctival hemorrhage) are more common in people with diabetes or high blood pressure, but neither condition causes the blood spots. Floaters in the eyes are also not related to high blood pressure. However, an ophthalmologist may be able to detect damage to the optic nerve caused by untreated high blood pressure.
  • Facial flushing: Facial flushing occurs when blood vessels in the face dilate. It can occur unpredictably or in response to certain triggers such as sun exposure, cold weather, spicy foods, wind, hot drinks and skin-care products. Facial flushing can also occur with emotional stress, exposure to heat or hot water, alcohol consumption and exercise — all of which can raise blood pressure temporarily. While facial flushing may occur while your blood pressure is higher than usual, high blood pressure is not the cause of facial flushing.
  • Dizziness: While dizziness can be a side effect of some blood pressure medications, it is not caused by high blood pressure. However, dizziness should not be ignored, especially if the onset is sudden. Sudden dizziness, loss of balance or coordination and trouble walking are all warning signs of a stroke. High blood pressure is a leading risk factor for stroke.

How to handle hypertension onboard

There are many factors which are important to become part of seafarers’ lifestyle to help prevent and manage hypertension, including:

  1. Control weight: Being overweight or obese increases the risk of cardiovascular disease, diabetes and high blood pressure
  2. Exercise regularly: Physical inactivity as part of seafarer’ lifestyle increases the risk of getting high blood pressure.
  3. Eat healthy: A diet high in salt consumption, as well as calories, saturated and trans fat and sugar, carries an additional risk of high blood pressure.
  4. Reduce or quit smoking and tobacco use: Using tobacco can cause blood pressure to temporarily increase and can contribute to damage arteries.
  5. Control stress: Too much stress can encourage behaviors that increase blood pressure, such as poor diet, physical inactivity, and using tobacco or drinking alcohol more than usual.

What is more, keeping a blood pressure diary in which seafarers record their blood pressure measurements, including the time of day and notations about events that might have affected the records, such as changes in medication, diet, or physical activity, could assist them intimately involved in their own care. However, seafarers should not use these recordings to self-medicate or make an attempt to diagnose themselves but they should always seek medical care in case any symptoms make their appearance.