Is 143 Blood Pressure High? What It Means for Your Health

A systolic reading of 143 mm Hg crosses the threshold for stage 2 hypertension under the current classification system used in the United States, which sets that cutoff at 140 mm Hg or higher. That puts it in the highest standard category of high blood pressure, not by a huge margin but clearly past the line. Whether that single number demands immediate action depends on several things, including how the reading was taken, whether it reflects your usual pressure, and what other health risks you carry.

Where 143 Falls on the Blood Pressure Scale

The 2017 American College of Cardiology and American Heart Association guidelines define four categories based on systolic and diastolic readings. Normal blood pressure is a systolic reading below 120 and diastolic below 80. Elevated blood pressure covers systolic readings of 120 to 129 with diastolic still below 80. Stage 1 hypertension starts at a systolic of 130 to 139 or diastolic of 80 to 89. Stage 2 hypertension begins at systolic of 140 or higher, or diastolic of 90 or higher.¹ A reading of 143 lands squarely in stage 2. Before this classification was updated, the older threshold for hypertension was 140/90, so 143 would have been considered high under that system too.

The systolic number (the top one) represents the pressure in your arteries when your heart contracts. The diastolic number (the bottom one) reflects pressure when the heart relaxes between beats. For people over 35, the systolic reading tends to be the stronger predictor of cardiovascular trouble. Large population studies have shown that at any given diastolic level, a higher systolic pressure corresponds to greater cardiovascular risk and shorter life expectancy.² So even if your diastolic is perfectly normal, a systolic of 143 deserves attention.

One Reading Is Not a Diagnosis

A single reading of 143 does not necessarily mean you have chronic hypertension. Blood pressure fluctuates throughout the day in response to activity, stress, caffeine, a full bladder, and even the temperature of the room. Measurement technique matters enormously. Poor technique alone can swing readings by more than 15 mm Hg in either direction.³ Crossing your legs, letting your arm hang unsupported, or resting your arm below heart level all push the reading higher.⁴

Cuff size is another common culprit. In a randomized crossover trial, people who needed a large or extra-large cuff but were measured with a regular cuff had their systolic reading inflated by about 5 mm Hg on average for the large-cuff group and by roughly 20 mm Hg for the extra-large group.⁵ If you have larger arms and the clinic uses a standard cuff without checking fit, a reading of 143 might actually be closer to 138 or lower. This is worth asking about.

Then there is white-coat hypertension, where your pressure spikes in a medical setting but is normal the rest of the time. Studies using 24-hour ambulatory monitors found that roughly one in five untreated patients with elevated office readings actually had white-coat hypertension.⁶ The flip side is masked hypertension, where your office readings look fine but your pressure runs high the rest of the day. Home monitoring catches some of these patterns, though ambulatory monitoring worn for a full day is more sensitive.

What a Sustained Reading of 143 Does to Your Body

If repeated measurements confirm that your systolic pressure consistently hovers around 143, the health implications are real. The relationship between blood pressure and cardiovascular risk is not a stepladder with safe on one side and dangerous on the other. It is a continuous slope that starts rising well below the hypertension threshold. A large analysis that mapped the risk of ischemic heart disease across different systolic levels found that compared to a systolic of 100, a systolic of 140 was associated with roughly 2.4 times the risk. By 150, the risk had tripled.⁷ At 143, you are sitting right in the zone where risk escalates substantially.

Systolic blood pressure is also an independent predictor of stroke and kidney disease. Multiple prospective studies confirm that the link between systolic pressure and these outcomes is continuous, graded, and not dependent on where your diastolic reading sits.⁸ For kidney disease specifically, guidelines generally recommend keeping systolic below 130 mm Hg to slow progression, with some suggesting a target as low as 120 in people who already have chronic kidney disease.⁹

There is also the brain to think about. Elevated blood pressure in midlife is tied to cognitive decline and a higher risk of dementia decades later. One long-running study found a three- to four-fold increase in dementia risk among people with untreated elevated blood pressure, and a separate study confirmed that the association holds over 25 years after accounting for other vascular risk factors.¹⁰ This makes blood pressure control in your 40s and 50s particularly consequential for cognitive health later on.

Why Your Blood Pressure Might Be Running at 143

Systolic blood pressure rises with age in most people, and arterial stiffening is the main driver. As artery walls lose elasticity over years of repetitive stress, they become less able to absorb the pulse of blood from each heartbeat. The result is a higher peak pressure with each contraction, and the reflected pressure waves from peripheral arteries arrive back sooner, adding to the systolic peak.¹¹ Research from the Framingham Heart Study showed that stiffer arteries predict future rises in systolic pressure and the development of hypertension, suggesting that stiffening drives the blood pressure up, not the other way around.¹²

Sodium intake plays a role, though its magnitude varies from person to person. High sodium leads to water retention and changes in blood vessel function that can raise pressure.¹³ But the degree to which salt affects your blood pressure depends heavily on salt sensitivity. Roughly a third of healthy people and over half of those with existing hypertension show exaggerated blood pressure responses to sodium. Salt sensitivity itself is an independent risk factor for cardiovascular disease.¹⁴ If you are not salt-sensitive, cutting sodium may produce only a modest change in your readings.¹⁵

Chronic stress is another contributor. When the body’s fight-or-flight system stays activated over long periods, it increases vascular tone and keeps arteries constricted. This heightened sympathetic nervous system activity is a well-established link between psychological stress and sustained high blood pressure.¹⁶ The combination of arterial stiffening, dietary factors, and chronic stress often works together, which is why single-cause explanations for a reading of 143 rarely tell the whole story.

Isolated Systolic Hypertension in Younger People

In older adults, a systolic reading of 143 with a normal diastolic number is a classic pattern driven by stiff arteries. In younger and middle-aged adults, this same pattern, called isolated systolic hypertension, is more complicated. Some younger people with high systolic readings have increased stroke volume, meaning their heart pumps a larger volume of blood per beat. Others have early arterial stiffening. The clinical significance of this pattern in younger people is still debated, and some researchers have suggested that a portion of these cases may reflect what they call “spurious” hypertension, where peripheral arm readings overestimate the true pressure in the central arteries.¹⁷ If you are under 40 with a systolic of 143 and a normal diastolic reading, your doctor may want a more detailed workup before starting treatment.

What Treatment Looks Like at This Level

At stage 2 hypertension, guidelines typically recommend both lifestyle changes and medication rather than lifestyle changes alone. For people whose blood pressure is more than 20/10 mm Hg above goal, clinical evidence supports starting with combination drug therapy rather than a single medication, because it achieves better control.¹⁸ A systolic of 143 when the target is under 130 (or under 120 for high-risk patients) is often in that range.

The SPRINT trial, which enrolled over 9,000 people at high cardiovascular risk but without diabetes, found that targeting a systolic pressure below 120 instead of below 140 reduced major cardiovascular events by about 25% and all-cause death by about 27%. The trial was stopped early because the benefit was so clear.¹⁹ That said, the more aggressive target also came with higher rates of side effects, so the right goal for you depends on your overall health profile.

Among drug classes, the main options include calcium channel blockers, RAS inhibitors (which include ACE inhibitors and ARBs), and thiazide diuretics. Cochrane reviews comparing these classes show broadly similar effects on overall death and total cardiovascular events, though each class has subtle trade-offs. RAS inhibitors, for example, appear to reduce heart failure risk compared to calcium channel blockers, but calcium channel blockers seem to have a slight edge in stroke prevention.²⁰ Your doctor weighs these differences against your individual risk factors.

Lifestyle Changes That Actually Move the Needle

Lifestyle modification at this level is not optional; it is additive to medication and sometimes sufficient to bring a borderline stage 2 reading like 143 back into the stage 1 or even elevated range. The DASH diet, which emphasizes fruits, vegetables, whole grains, lean protein, and low-fat dairy while limiting sodium, saturated fat, and added sugars, has strong trial evidence behind it for lowering blood pressure. Multiple clinical trials, including the DASH-Sodium study and the OmniHeart trial, have confirmed its ability to reduce blood pressure.²¹ When the DASH diet is combined with aerobic exercise, there are added benefits for both blood pressure and neurocognitive function.²²

Magnesium supplementation is worth mentioning because it comes up in a lot of online health advice. A meta-analysis of randomized, double-blind, placebo-controlled trials found that magnesium supplementation at about 370 mg per day for three months lowered systolic pressure by about 2 mm Hg and diastolic by about 1.8 mm Hg compared to placebo.²³ That is real but small. If you are deficient in magnesium, supplementation may help at the margins, but it is not going to replace medication for someone at 143.

Monitoring at Home and What to Watch For

If your doctor confirms stage 2 hypertension, you will likely be asked to monitor your blood pressure at home. How useful that monitoring is depends partly on how it is integrated into your care. A large retrospective analysis found that remote patient monitoring programs were associated with meaningful improvements: systolic blood pressure dropped by an average of about 7 mm Hg across all patients, and by nearly 17 mm Hg for those starting with stage 2 hypertension.²⁴ A randomized controlled trial testing remote monitoring with professional guidance found that after two years, the remote group had systolic readings about 2.7 mm Hg lower than usual care, and nearly 70% had reached their target blood pressure.²⁵ Simply handing someone a home cuff without structured follow-up and medication adjustments appears less effective. One randomized trial found that remote monitoring without additional clinical support did not significantly improve blood pressure control compared to usual care.²⁶ The takeaway is that the monitor is a tool, not a treatment. It works best when someone on the clinical side is actually reviewing your numbers and adjusting your therapy.

The Nighttime Blood Pressure Pattern Most People Miss

One aspect of blood pressure that rarely comes up in routine care is what happens while you sleep. In most people, blood pressure dips by 10 to 20 percent at night compared to daytime levels. When this dip is absent or blunted, it is called a “non-dipping” pattern, and it carries risk independent of your average 24-hour blood pressure. People with persistent non-dipping have worse kidney and cardiovascular outcomes regardless of what their daytime readings look like.²⁷ A 21-year follow-up study found that people who were consistently non-dipping had about four times the risk of cardiovascular events compared to those who dipped normally, even after adjusting for office and ambulatory blood pressure levels.²⁸

Non-dipping is also linked to faster progression of kidney damage and left ventricular thickening.²⁹ You cannot detect this pattern with an office reading or a standard home monitor. It requires ambulatory blood pressure monitoring, where a cuff inflates automatically throughout the day and night over a full 24-hour cycle. If you have stage 2 hypertension that is difficult to control, sleep apnea, kidney disease, or diabetes, asking your doctor about a 24-hour ambulatory study may be worthwhile.

Blood Pressure During Pregnancy

A systolic reading of 143 during pregnancy carries different implications than the same reading in a non-pregnant adult. The traditional threshold for diagnosing hypertension in pregnancy remains 140/90, and a recent cohort study found that readings below 140/90 were reliable for ruling out preeclampsia, while readings at or above 140/90 were useful for ruling it in.³⁰ A reading of 143 in a pregnant person, particularly after 20 weeks, warrants prompt clinical evaluation because it is above the threshold where preeclampsia becomes a real concern. Blood pressure variability during pregnancy, meaning how much readings swing from one measurement to the next, may also help identify women at elevated risk of complications.