Hyperparathyroidism: High Calcium, Bone Loss, and When Surgery Is Needed

When your blood calcium stays too high for too long, it doesn’t just affect your bones-it can fog your brain, wreck your kidneys, and leave you exhausted even after a full night’s sleep. This isn’t just a lab result. It’s hyperparathyroidism, a condition that quietly damages your body for years before anyone connects the dots.

What Exactly Is Hyperparathyroidism?

Your parathyroid glands are four tiny pea-sized organs tucked behind your thyroid in the neck. They don’t make hormones for mood or metabolism. They control calcium-the mineral your bones, nerves, and muscles depend on. When these glands go rogue, they pump out too much parathyroid hormone (PTH). That hormone tells your bones to break down, your kidneys to hold onto calcium, and your gut to absorb more of it from food. The result? Blood calcium climbs above 10.5 mg/dL. Normal is 8.5-10.2.

This isn’t rare. About 100,000 Americans get diagnosed with primary hyperparathyroidism every year. Women are three times more likely than men. African Americans have higher rates too. Most cases happen after age 50, but younger people get it too-especially if there’s a family history.

The most common cause? A benign tumor called an adenoma on one gland. It’s not cancer. It’s just stuck in the "on" position. In 15% of cases, all four glands are enlarged (hyperplasia). Less than 1% are cancerous. And here’s the kicker: many people don’t feel anything at first. That’s why it often shows up on routine blood work.

How High Calcium Destroys Your Bones

Your bones aren’t just scaffolding. They’re active storage units for calcium. When PTH stays high, your body treats your skeleton like a cash machine. Osteoclasts-cells that break down bone-go into overdrive. Every year, you lose 2-4% of bone density in your spine and hips. That’s faster than most people lose bone with aging.

By the time someone’s diagnosed, many already have osteoporosis. A DXA scan (the same one used for routine bone checks) will show a T-score of -2.5 or lower. That means your fracture risk is 30-50% higher than someone your age with normal calcium.

You might not feel your bones weakening until you fall. A simple slip on ice, stepping off a curb wrong, or even coughing hard can cause a vertebral fracture. These often go unnoticed-no sharp pain, just a slow loss of height or a new curve in your back. That’s why hyperparathyroidism is called a silent thief.

It’s Not Just Bones: The Other Symptoms

People with high calcium often describe feeling "off" for years before getting answers. They think it’s aging, stress, or depression. Common signs include:

• Chronic fatigue that doesn’t improve with rest
• Brain fog-trouble concentrating, forgetting names, losing your train of thought
• Bone pain, especially in the back, hips, or legs
• Frequent kidney stones (calcium builds up in urine)
• Nausea, loss of appetite, constipation
• Depression or anxiety that doesn’t respond to therapy or meds

One patient on EndocrineWeb said: "After seven years of being told I was just depressed, my calcium was 11.8 and PTH was 142. After surgery, it felt like someone turned my brain back on." That’s not anecdotal. Studies show 78% of patients report fatigue and bone pain as their worst symptoms. Cognitive issues affect 65%. Many return to work or school after surgery because their mental clarity comes back.

How Doctors Diagnose It

Diagnosis starts with two simple blood tests: calcium and PTH. But here’s where it gets tricky. If your calcium is high and your PTH is normal or just slightly elevated, that’s still abnormal. Your parathyroid glands should shut off when calcium is high. If they don’t, something’s wrong.

You need two high calcium readings at least a week apart to confirm. No single test catches it all. Doctors also check:

• Vitamin D levels (low vitamin D can mask the problem)
• Kidney function (creatinine, eGFR)
• Phosphorus (often low in hyperparathyroidism)

Then comes imaging. A sestamibi scan (a nuclear medicine test) finds the bad gland in 90% of cases. Ultrasound is cheaper and non-radiation, catching about 85%. For complex cases, 4D-CT gives 95% accuracy. These aren’t optional-they’re required before surgery to avoid exploring both sides of the neck unnecessarily.

When Surgery Is the Only Real Cure

Medication can lower calcium a little, but it doesn’t fix the root problem. Cinacalcet helps in kidney disease-related cases but only works in 20-30% of primary hyperparathyroidism. Bisphosphonates can rebuild some bone, but they don’t touch the high calcium.

Surgery-parathyroidectomy-is the only cure. And it’s highly effective. For a single adenoma, success rates are 95-98%. Most patients go home the same day. The procedure takes 1-2 hours. Surgeons use a tiny incision and often monitor PTH levels during surgery. If the hormone drops by more than 50% within 10 minutes after removing the gland, you’re cured.

The Endocrine Society’s 2023 guidelines say surgery is recommended if you have:

• Calcium more than 1 mg/dL above normal
• Low kidney function (eGFR under 60)
• Bone density T-score of -2.5 or worse
• Age under 50

Even if you have no symptoms, these criteria matter. Untreated, your fracture risk keeps climbing. And once you’re over 60, the chance of developing kidney stones or heart rhythm problems rises too.

What Happens After Surgery

Most people feel better within days. Fatigue lifts. Brain fog clears. Kidney stone episodes drop by 92% in the first six months. Bone density starts improving within a year-3-5% in the spine, 5-8% by year two.

But there’s a catch. After removing a gland that’s been overworking for years, your body temporarily forgets how to make enough calcium. About 30-40% of patients get temporary low calcium (hypocalcemia). That means tingling in fingers, muscle cramps, or even seizures in rare cases. It’s managed with calcium and vitamin D supplements for a few weeks to months.

In rare cases, if all four glands were overactive, some tissue is left behind. That’s why people with multigland disease need annual calcium checks for life. Recurrence risk is 5-10% versus 2-3% for single-gland cases.

Why Some People Delay Surgery-and What They Lose

Many patients wait. They’re scared of voice changes. They think "it’s not that bad." But the truth? Recurrent laryngeal nerve injury (which affects voice) happens in less than 1% of cases when done by experienced surgeons. That’s lower than the risk of a car accident on a daily commute.

A 2022 Mayo Clinic study found that patients with calcium over 12 mg/dL for years had a 22% chance of lingering fatigue and brain fog after surgery. Those with calcium under 11 mg/dL? Only 8%. The longer you wait, the more damage becomes permanent.

And it’s not just your bones. High calcium strains your heart, increases blood pressure, and raises the risk of atrial fibrillation. It’s linked to cognitive decline over time. You’re not just protecting your skeleton-you’re protecting your brain and heart.

What You Can Do Now

If you’ve been told your calcium is high:

• Don’t ignore it. Get a second blood test in a week.
• Ask for PTH, vitamin D, and kidney function tests.
• If confirmed, see an endocrinologist or an endocrine surgeon-not just your primary care doctor.
• Get imaging before making any decisions.
• Stop taking thiazide diuretics (like hydrochlorothiazide) if you’re on them-they worsen hypercalcemia.
• Take 1,200 mg of calcium daily from food or supplements (yes, even though your levels are high-your bones are starving).
• Walk 30 minutes a day. Weight-bearing exercise helps rebuild bone.

You don’t need to rush into surgery. But you do need to act. This isn’t a condition that gets better on its own. It gets worse.

What’s New in 2025

AI is now helping radiologists read sestamibi scans with 98% accuracy-cutting false positives by 35%. A new drug called etelcalcetide showed 45% PTH reduction in trials and may soon be approved for primary cases. Genetic testing is now recommended for anyone under 40 or with family members who had parathyroid or thyroid tumors.

The message is clear: earlier detection, smarter imaging, and faster surgery mean fewer broken bones, fewer kidney stones, and more people getting their lives back.