St. Louis police are asking for the public's help finding a 73-year-old man with dementia who disappeared after leaving his home Thursday afternoon and failed to show up for an appointment. The St. Louis Metropolitan Police Department issued an Endangered Silver Advisory for Terry Zarbo, who was last seen leaving his residence on Marquette Avenue in the Northampton neighborhood around 2 p.m. He has had no further contact with anyone since.
According to First Alert 4, Zarbo was last seen driving a silver 2015 GMC Canyon bearing Missouri license plate 0AAT60. Police describe him as a white man standing 5 feet 11 inches tall and weighing 165 pounds, with brown and gray hair and brown eyes. He was last seen wearing a gray shirt, gray shorts, and a bandage on one leg.
Zarbo is diagnosed with dementia and polymyositis, and he takes blood-thinning medication, all factors that compound the danger of his disappearance. Police are asking anyone who spots Zarbo, his vehicle, or has related information to call 911, or to contact SLMPD at 314-444-0100 or the nearest law enforcement agency.
Why the Silver Advisory Threshold Applies
Missouri's Endangered Silver Advisory system exists specifically for cases like this one. Under Missouri Revised Statutes 650.025, the advisory can be activated when a missing person is at least 60 years old, is believed to suffer from dementia or cognitive impairment, and enough descriptive information exists to broadcast to the public. Zarbo's profile met that threshold, triggering a response that goes well beyond a routine missing-person report.
Once police take a missing person report in Missouri, state law requires immediate action. Under Section 43.401 RSMo, agencies must log the entry into the Missouri Uniform Law Enforcement System and the National Crime Information Center without any mandatory waiting period, meaning there is no delay before a case like Zarbo's enters statewide and national databases. When an advisory is activated, multi-agency protocols also notify law enforcement statewide, media outlets, the Department of Health and Senior Services, and the Missouri Department of Transportation, which can display highway message board alerts where feasible, according to a resolution published by the Nixa Police Department.
A Medical Profile That Raises the Stakes
Zarbo's diagnoses add urgency beyond the typical wandering case. Polymyositis is a rare inflammatory muscle disease in which the immune system attacks skeletal muscles, primarily causing progressive, symmetric weakness in the hips, thighs, and shoulders, according to the Mayo Clinic. That kind of muscle weakness could make it difficult for him to move or seek help if he becomes stranded.
His blood-thinning medication adds another layer of risk. Safety protocols from the VHA National Center for Patient Safety state that missing individuals on anticoagulant medications face elevated medical risks because unmonitored falls or physical trauma can trigger severe internal bleeding, according to guidance from the VHA National Center for Patient Safety. Any fall or crash involving Zarbo would carry more serious consequences than it might for someone without that condition.
Wandering Is Common, and Time Matters
Zarbo's case fits into a broader pattern among people living with dementia. Roughly 60% of people with dementia will wander at least once during their illness, a behavior that can occur unpredictably at any stage of cognitive decline, per statistics from the Alzheimer's Association. Research highlighted by the Cleveland Clinic shows that missing dementia patients face severe safety risks, with half of wandering individuals suffering serious injury or death if they are not located within 24 hours.
Zarbo went missing from Northampton, a 0.92-square-mile residential neighborhood in south St. Louis bounded by South Kingshighway Boulevard, Chippewa Street, Hampton Avenue, and Scanlan and Connecticut avenues, home to 7,489 residents as of the 2020 Census, according to the City of St. Louis. Nearly half of households in the neighborhood, 49.6%, consist of individuals living alone, a rate significantly higher than most U.S. communities, per data from NeighborhoodScout.
Statewide, missing-person cases like Zarbo's are not uncommon this year. The Missouri State Highway Patrol has recorded 1,765 missing adult cases reported across the state in 2026 through early August, with 124 adults still actively missing from those reports. It remains unknown where Zarbo was headed for his appointment, which direction he traveled from Marquette Avenue, or whether license plate readers or highway cameras have detected his GMC Canyon. Hoodline previously covered a similar Florissant case involving an elderly man with dementia who disappeared after an appointment.
