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Adult Audiograms
A 30-minute hearing test, with a booth, headphones, and a button you press when you hear the beep — that's the substance, and it is more consequential than it sounds. Untreated mid-life hearing loss is the largest single changeable risk factor for dementia in the 2024 Lancet model, ahead of high blood pressure, smoking, and physical inactivity. Most people who have it don't know — high-frequency loss erodes the consonants in speech, so the world feels mumbly long before it feels quiet, and the average gap from "could benefit from a hearing aid" to "owns one" is nearly nine years.
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The headline reason: hearing loss is the biggest fixable contributor to dementia risk we know of in mid-life, and an audiogram is the gateway to treating it. The test itself is cheap, painless, often covered by insurance, and takes under an hour every few years. It is also the only way a noise-exposed worker keeps a future hearing-loss claim alive, and the only way someone about to start cisplatin or aminoglycoside antibiotics knows what their ears could afford to lose. The catch is honest: a hearing test changes nothing on its own — it works because most people who learn they have a loss act on it, and the ~70% who don't get nothing.

An audiogram is three tests stitched together. The first is pure-tone audiometry: in a soundproof booth, the audiologist plays beeps at each of six pitches — roughly the low rumble of a foghorn up to the highest note a child can hear — once through headphones, then again through a small vibrator pressed against the bone behind your ear. Headphones test the whole hearing pathway; the bone vibrator skips your eardrum and middle ear and goes straight to the inner ear. If the two numbers match, any loss is in the inner ear or nerve. If the headphone number is worse, something is blocking the outer or middle ear — wax, fluid, a stiffened bone — and that block is usually fixable.

The second is speech testing. The audiologist reads or plays you words at decreasing volume and asks you to repeat them; the lowest volume at which you can still get the easy two-syllable ones half the time is your speech-reception threshold. Then they read single words at a comfortable volume and score how many you catch. This is the part of the test that captures the thing you actually care about — whether you can follow a conversation — and the number that comes out is the one a hearing aid is trying to move. It has one blind spot worth knowing: some people clear every threshold and still can't follow speech in a noisy room — hidden hearing loss — which only surfaces on a dedicated speech-in-noise test you have to ask for.

The third is tympanometry: a soft plug in the ear canal that puffs air and measures how your eardrum moves. It's the quickest piece, takes about 30 seconds per ear, and rules in or out fluid, infection, or eardrum perforation in a way the beep test can't.

The result is plotted on the actual audiogram — the chart with frequency across the bottom and loudness down the side, with each ear marked separately. The closer your line is to the top of the chart, the better; the steeper it slopes downward as you move right, the more high-frequency loss you have. The classic age-related pattern — presbycusis — is a gentle slide from left to right that starts in your fifties and steepens through your seventies. The classic noise-damage pattern is a notch carved out at 4,000 Hz — exactly where rifle shots, power tools, and concerts dump their energy Cunningham & Tucci 2017.

What the test actually changes

The dementia link is the biggest single reason this entry exists. The 2024 update of the Lancet Commission on dementia prevention named hearing loss the largest single changeable risk factor in mid-life — bigger than smoking, bigger than blood pressure, bigger than physical inactivity — and credited it with about 7% of all dementia cases worldwide Livingston et al. 2024. The original signal came from a 12-year follow-up of nearly 640 adults in Baltimore: every 10-decibel worsening of hearing thresholds — roughly the gap between "normal" and "noticing trouble in restaurants" — raised the risk of developing dementia by about a quarter Lin et al. 2011.

For years the obvious counter-question was whether treating the hearing loss did anything to the risk, or whether bad hearing and bad memory just travelled together. The ACHIEVE trial settled that, partly.

Two other downstream payoffs are smaller but real. Adults with untreated hearing loss are more likely to be depressed than adults of the same age who hear normally — a pattern that holds across 35 studies and ~147,000 people, mostly driven by social isolation Lawrence et al. 2020. And in the workplace: pure-tone audiometry has been the legally recognised reference test for noise-induced hearing loss for over forty years, and an employee without a baseline on file is, in practice, an employee without a hearing-loss compensation claim 29 CFR 1910.95.

The honest skeptic position: the US Preventive Services Task Force looked at the same evidence in 2021 and declined to recommend asymptomatic screening for adults 50+, calling the evidence "insufficient" — not because the test is bad but because the chain from "we found a mild loss" to "the patient bought a hearing aid and used it" breaks at roughly the rate of seven in ten USPSTF 2021. The Task Force is not arguing the test doesn't work. It is arguing that most people who learn they have a mild loss do nothing about it, which makes mass screening in primary care a poor use of public-health dollars. A reader who would actually act on the result is in a different position from the population the Task Force was rating.

When to get tested, and how often

The default adult schedule, drawn from professional audiology recommendations rather than primary-care screening rules: one baseline test by age 50, repeats every three years after 50, and every year after 70 or whenever something changes — a new ringing in one ear, a friend repeatedly asking why you have the TV so loud, a sense that restaurants have gotten harder. People with risk factors get on the schedule earlier: regular noise exposure (occupational, recreational, military), family history of early hearing loss, ototoxic medication on the horizon, diabetes, or a cardiovascular event.

What happens in the room: you sit in a small sound-treated booth, wearing headphones or foam earbuds. The audiologist plays beeps at one pitch and one volume at a time and asks you to press a button (or raise your hand) every time you hear one. They walk down in volume until you stop hearing the beep, then back up; that crossover is your threshold for that pitch in that ear. They repeat across six pitches per ear with headphones, then again with the bone vibrator behind your ear, then the speech words, then the air-puff tympanometry. Total time: 30–60 minutes. No needles, no medication, no recovery period.

Cost in the US is roughly $50–250 out of pocket at a private audiology clinic if you pay cash. Medicare Part B covers the diagnostic audiogram when a doctor orders it for a medical reason — including any of the changes listed above — with the usual 20% co-insurance after the annual deductible. Since 2023, Medicare also allows you to see an audiologist directly once a year for diagnostic hearing testing without a doctor's order. Commercial insurance is similar; most plans cover an ordered audiogram. Hearing aids themselves are a separate cost question — see the practicalities section.

If you work around noise

Different rules apply to anyone whose job exposes them to an average of 85 decibels averaged over an eight-hour shift — roughly the level of a busy city street, a running lawnmower, or a forklift. Construction, manufacturing, agriculture, oil and gas, music venues, military service: all in. Under US occupational safety law, the employer must arrange a baseline audiogram within six months of your first day on the job, repeat it every year for as long as you stay in the noisy job, and pay for both tests. The baseline has to be preceded by at least 14 hours of quiet — meaning either a day off or solid hearing protection in the run-up — so it captures your real hearing, not the temporary dip after a shift 29 CFR 1910.95.

The number the employer is watching is the standard threshold shift: a 10-decibel drop from your baseline, averaged across the three pitches noise damages first (2, 3, and 4 kHz), in either ear. Cross that line and your employer must notify you within 21 days, refit your hearing protection, retrain you, and in many cases log the case on the federal OSHA injury record.

Loud hobbies follow the same biology even if no employer is involved. Sustained recreational noise — gunfire without ear protection, motorcycle commuting, music played through earbuds above 80% volume for hours daily, regular concert attendance without plugs — produces the same 4-kHz notch on the audiogram as a factory job. If that describes you, run the standard adult cadence above and add a baseline now rather than at 50.

From audiogram to hearing aid

An audiogram is a measurement, not a fix. What it does — for the consequence most people in the catalogue's reader range care about — is tell you whether you qualify for a hearing aid and what kind.

The standard severity bands are simple. Average thresholds across the speech frequencies of 0–25 decibels count as normal. 26–40 is mild loss — the band where consonants start dropping in noisy rooms but conversation in a quiet kitchen is still fine. 41–55 is moderate — TV volume creeps up, group conversation gets hard. 56–70 is moderately severe; 71–90 is severe; over 90 is profound. Mild and moderate losses are hearing-aid territory; severe and profound losses get evaluated for a cochlear implant, a surgically placed device that bypasses damaged inner-ear hair cells entirely.

Until 2022 the only path to an amplification device in the US was an audiologist visit, a custom fitting, and a $4,000–6,000 pair of devices, usually not covered by Medicare. In October 2022 the FDA created a new category of over-the-counter hearing aids for adults 18 and over with perceived mild to moderate loss FDA 2022. These sell for $200–1,500 a pair, at pharmacies and online, with no prescription. The audiogram is still useful: it tells you whether you're in the mild-to-moderate range OTC devices are designed for, and rules out the conductive or asymmetric findings that need an ENT instead of an amplifier.

What people get wrong

"I'd know if I were losing my hearing." The most common belief, and the wrongest one. Age-related hearing loss starts at the high frequencies — the pitches where consonants live — and creeps down toward the speech range over years. The world doesn't get quieter; it gets mumbly. People with measurable loss describe it as "everyone mumbles," "restaurants are impossible," "my wife needs to face me when she talks" — never as "I can't hear." The average gap between qualifying for a hearing aid and owning one is nearly nine years, and most of that gap is people not knowing they qualify.

"Hearing aids are for old people." Two things have shifted in the last few years. Devices are now small, often invisible at conversational distance, and Bluetooth-connected to your phone the way wireless earbuds are. And the FDA's 2022 rule means a 40-year-old with mild loss from years of headphones-on-the-subway can buy a $300 device at a pharmacy without ever seeing a doctor FDA 2022. The stigma is doing real damage at this point — the strongest evidence on dementia delay involves people who actually wear the devices for years Lin et al. 2023.

"My doctor checked my hearing at my last physical." Almost never. The "whisper test" or rubbing fingers next to your ear catches severe loss only and misses mild and moderate loss almost entirely. The same applies to single-question screens ("are you having trouble with your hearing?") — they catch the people who already know. A real audiogram is a different test in a different room with different equipment.

"Screening is settled." It isn't. The US Preventive Services Task Force has not been able to recommend routine asymptomatic screening of adults 50+ because the chain from finding a mild loss to actually treating it breaks at population scale USPSTF 2021. Audiology and otolaryngology professional bodies disagree and recommend baseline plus periodic testing. Both sides agree the test itself is solid; they disagree about whether telling everyone to get it produces population-level benefit. For an individual reader who would actually act on a finding, this debate doesn't change the calculus much.

What happens if you keep skipping it

In the short run, nothing. Untreated mild hearing loss feels like normal aging — restaurants get harder, group dinners get tiring, you turn the TV up a notch, your partner repeats themselves twice a day. Nobody around you sees a problem yet. You don't either.

Over the next decade, that floor moves. You stop accepting invitations to noisy places because they're exhausting. Phone calls get shorter. Your circle gets smaller in ways you don't quite track to the hearing — it feels like everyone got busier. Your spouse starts answering for you in conversations because by the time you've parsed what was asked, the moment has passed. People you used to enjoy being around start telling someone else first. By the time you decide to do something about it, the social shape of your life has already reorganised around the loss Lawrence et al. 2020.

Over the decade after that, the cognitive bill comes due. The same midlife untreated hearing loss that made dinners exhausting in your sixties is — in the strongest current model — the largest single thing under your control that raises your dementia risk in your seventies Livingston et al. 2024. Not because hearing loss directly damages the brain, but because parsing speech when the signal is degraded is constant cognitive work, because withdrawing socially removes the daily novelty the brain needs, and because the cells in your inner ear and the cells in your hippocampus respond to a lot of the same vascular and metabolic insults. Adults who treated their hearing loss in the ACHIEVE trial slowed their three-year cognitive decline by nearly half — but only the ones who started at higher risk, and only after the devices were actually fitted and used Lin et al. 2023.

For noise-exposed workers there's a second timeline running in parallel. Each year of unprotected high-volume work without a baseline on file is a year of hearing damage that can't be claimed, can't be compensated, and can't be tracked back to the employer. By the time the loss is severe enough that you notice, the documentation needed to do anything about it doesn't exist 29 CFR 1910.95.

What changes if you treat it

Within a few weeks of fitting hearing aids — the practical outcome of an audiogram that finds a treatable loss — most people report the same set of small shifts. Restaurants stop being adversarial. You stop saying "what?" reflexively. The TV goes down two notches and your partner stops repeating themselves. The afternoon fatigue that you assumed was age turns out to be partly the cost of constant listening effort, and it eases off Lawrence et al. 2020.

Within a few months, the social shape starts to repair. The neighbours' barbecue stops being a thing you dread. You take phone calls you'd been avoiding. People who'd quietly stopped including you in plans don't even notice they've started again. The repair is partial — you don't get the years back — but the direction reverses.

Within a few years, in the higher-risk adults the ACHIEVE trial recruited, the cognitive trajectory measurably bends. Three-year cognitive decline cut by almost half compared with the control group — the only RCT-grade evidence for a behavioural intervention with that effect size in older adults at risk for dementia Lin et al. 2023. The effect was real in the high-risk cohort and not detectable in the lower-risk one, which is honest: if you're a healthy 70-year-old with no other dementia risk factors, treating mild hearing loss is unlikely to be the single thing that changes your trajectory. If you've already got cardiovascular disease, diabetes, lower education, or a family history, it might be.

For the noise-exposed worker, the payoff is more linear and shows up earlier: every standard-threshold-shift detection on the annual audiogram is a moment your employer is legally required to refit your protection, retrain you, and re-evaluate the noise source — a brake that gets pulled before the next year of damage 29 CFR 1910.95. For the chemotherapy patient, an audiogram during treatment that shows a meaningful shift can prompt an oncologist to drop the cisplatin dose or switch to a less-ototoxic agent — preserving hearing that, once lost to platinum, doesn't come back Kohrman et al. 2020.

How this goes wrong in practice

The most common failure: getting a clean audiogram, learning you have mild loss, and doing nothing. This is the failure mode the US Preventive Services Task Force was worried about — and it's also the reason the dementia-prevention payoff is conditional. A filed report doesn't slow decline; a worn device does. If you're not the kind of person who'd buy and wear amplification on a mild-loss finding, the test buys you a baseline and not much else right now.

The next most common: a primary-care office "checks your hearing" as part of an annual physical, finds nothing, and you take that as a real screen. It almost never is — a whisper test or a single screening question catches severe loss only and routinely misses mild and moderate loss. If you want an actual audiogram, it happens in a soundproof booth with calibrated equipment, run by an audiologist; it's not a five-second part of a physical.

The third: an audiogram surfaces a meaningful difference between the two ears, and nobody chases it. Asymmetric sensorineural loss — one ear measurably worse than the other on bone-conduction testing — is the audiogram's strongest reason to order an MRI of the inner-ear canal, looking for a vestibular schwannoma. Caught small, the tumour is monitored or treated with focused radiation and your hearing is preserved. Caught large, surgery becomes the option and hearing in that ear usually goes. Don't let an asymmetric reading sit in a file.

The fourth, specific to noise-exposed workers: a "baseline" taken without the required 14-hour quiet period in front of it. That baseline records your already-fatigued hearing as your normal — and from then on, every annual test compares against that lowered bar, masking real shifts. If your first day on a noisy job included an audiogram in the on-site occupational-health office that afternoon, ask for a repeat under proper conditions 29 CFR 1910.95.

Adjacent topics

Hearing-aid selection and fitting are downstream of the audiogram and a separate decision. Tinnitus — persistent ringing — often shows up alongside hearing loss and gets its own evaluation. Vestibular testing for balance disorders uses similar equipment but answers a different question. Newborn hearing screening is universal in the US but unrelated to the adult cadence here. Hearing protection — earplugs, earmuffs, in-ear monitors for musicians — is the upstream prevention story for noise-induced loss.

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