Blood Clots in Older Adults: Risks, Symptoms, Prevention, and Treatment (2025 Guide)

The scary thing about a blood clot is how ordinary the early signs can look-an achy calf, a little swelling, a cough that won’t quit. In people over 65, those small changes can be the red flags that matter. This guide shows you how to spot trouble early, lower the odds of a clot forming, and understand treatment choices without getting lost in jargon. I live in Canberra, and in my house the rule is simple: if a symptom feels off and sticks around, we act. That mindset has saved more than one neighbour on our street.

What you’ll get here: crisp signs to watch for, a prevention plan you can actually follow at home or in hospital, and a no-nonsense breakdown of treatments your doctor might recommend. I’ll stick to what’s evidence-backed and practical. You’ll also find checklists, a quick table for medicines, and plain answers to the questions families ask at 2 a.m.

TL;DR and what to watch for

• blood clots in the elderly are common and dangerous but largely preventable. Risk rises sharply after 70, especially after surgery, hospital stays, or long immobility.
• Know the signs: DVT in the leg (one-sided swelling, pain, warmth, redness); PE in the lungs (sudden shortness of breath, chest pain that worsens with a deep breath, fast heartbeat, coughing up blood). Call emergency services if PE is suspected.
• Move every hour while awake, stay hydrated, and use prescribed blood thinners or compression devices after surgery or during hospital stays. For long trips, walk and do calf squeezes.
• Treatment is usually anticoagulation (blood thinners) for at least 3 months; longer if the clot was “unprovoked” or the risk stays high. Bleeding risk and kidney function guide the drug choice.
• In Australia, hospitals use VTE risk checks on admission. Ask, “What’s our clot-prevention plan?”

Quick orientation. “Blood clots” usually means venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE). Incidence climbs with age-studies show approximately 5-7 events per 1,000 people each year in adults over 80. The Centers for Disease Control and Prevention reports roughly half of clots happen during or within three months of a hospital stay or surgery. The World Health Organization places VTE among the top cardiovascular killers after heart attack and stroke.

“About half of blood clots occur during or within three months of a hospital stay or surgery.” - Centers for Disease Control and Prevention.

Key risks you can’t change: age, prior clot, cancer, inherited clotting disorders. Risks you can tackle: immobility, dehydration, recent surgery (especially hip/knee), hospitalisation, hormone therapy, smoking, obesity, heart failure, and kidney disease. In real life, clots show up when two or three risks line up-like a long flight after a knee replacement. That’s why the prevention plan below blends movement, hydration, and medication when appropriate.

Prevention that works at home, in hospital, and on the move

Think in layers: move, hydrate, prevent stasis with compression when advised, and use medicines when risks are high. My Labrador, Max, doesn’t care about VTE, but his demand for two walks a day is perfect prevention. Small, consistent steps matter.

Daily home routine (simple, sustainable):

• Move every hour: 3-5 minutes. March in place, do 20 calf raises, or slow laps up the hallway. If you use a walker, it still counts.
• Hydrate: aim for pale-yellow urine. Most older adults do well with 6-8 cups a day unless your doctor limits fluids for heart/kidney reasons.
• Leg check: once a day, compare calves. If one is larger, hotter, redder, or more tender-especially after a long sit-call your GP or go to urgent care.
• Medications: take prescribed blood thinners exactly as directed. Don’t skip doses. If you miss one, follow your doctor’s advice on what to do next.
• Feet up: if you sit a lot, elevate calves so heels rest on a pillow and knees are slightly bent-this reduces venous pressure.

Hospital and post-surgery (high-impact moves):

• Ask on admission: “What’s my VTE risk score and plan?” Most Australian hospitals follow the VTE Clinical Care Standard with risk checks and tailored prevention.
• Use what’s ordered: this may include low-dose blood thinners (e.g., heparin or a direct oral anticoagulant) and intermittent pneumatic compression sleeves.
• Early mobilisation: out of bed as soon as it’s safe, even if it’s just sitting in a chair the first day.
• After hip/knee surgery: prevention often continues for 2-6 weeks after discharge. Know your stop date and who reviews it.
• Watch for bleeding: nosebleeds, blood in urine or stools, unusual bruising. Report promptly; don’t stop anticoagulants without advice.

Travel (car, coach, plane):

• For trips longer than 4 hours, set an hourly timer to stand up or do seated ankle circles and calf squeezes.
• Choose aisle seats when possible; walk the aisle every hour.
• Wear graduated compression stockings if advised. They can help venous return on long flights.
• Skip dehydrators: go easy on alcohol and sedatives that keep you still and dry you out.
• High-risk travelers (recent surgery, prior clot, cancer): ask your doctor about a one-off preventive dose before travel.

Simple heuristics you can remember:

• The 3-60 rule: move for 3 minutes every 60 minutes while awake.
• The 2-day check: any new one-sided leg swelling or pain that persists beyond 48 hours deserves medical review.
• Post-op doubling: if you had lower-limb surgery, double your movement reminders for the first month.

What about compression stockings day to day? They can ease leg symptoms and swelling, but they aren’t a magic shield. Use them if your clinician recommends them or if you find they help your comfort. After a DVT, routine use to prevent long-term symptoms is no longer standard for everyone; it’s now tailored to your situation.

Treatment options and how doctors decide

First, how clots are confirmed. For suspected DVT in the leg, the usual test is a venous ultrasound. For suspected PE in the lungs, doctors often use a CT pulmonary angiogram. Blood tests like D-dimer can help rule out clots in low-risk cases. Chest X-rays and ECGs look for other causes of symptoms.

The backbone of treatment is anticoagulation-“blood thinners” that stop the clot from growing while your body slowly dissolves it. Duration depends on why the clot formed and your bleeding risk. Here’s the pattern used in Australia and internationally:

• Provoked clot (e.g., after surgery or a clear temporary risk): anticoagulation for 3 months.
• Unprovoked clot or ongoing risk (e.g., active cancer): at least 3 months, often extended or indefinite if bleeding risk is acceptable.
• Recurrent clot: usually extended therapy.

Common medicines, at a glance:

Picking the right drug is a balancing act. Doctors look at kidney function, weight, cancer status, other medications, fall risk, and how easy it is for you to get tests. In older adults, apixaban is commonly chosen because it has a lower major bleeding rate in several studies and is easier to use than warfarin. If you have active cancer, LMWH or certain DOACs are often first-line. If you need a procedure soon, a short-acting heparin infusion may be used in hospital.

Worried about falls? The data are reassuring: for most people, the benefit of preventing a life-threatening clot outweighs the bleeding risk from a typical number of falls. Clinicians still individualise this, but “fall risk alone” rarely means “no anticoagulant.”

What about big clots in the lungs? For massive or high-risk PE (unstable blood pressure, signs of shock), doctors consider thrombolysis (a clot-busting drug) or catheter-based treatments. These carry higher bleeding risk, so they’re reserved for specific situations. For extensive DVT that threatens a limb, selected patients may get catheter-directed therapy, again case by case.

IVC filters-small metal devices placed in the large vein-are rarely used now. They may be considered if you have a confirmed DVT/PE and absolutely cannot take blood thinners. Filters come with their own risks and should be removed once it’s safe to resume anticoagulation.

Symptoms after treatment starts: leg pain and swelling usually improve over days to weeks, not hours. Breathlessness after PE can take several weeks to settle. If symptoms worsen or new chest pain or bleeding appears, seek urgent care.

Food and drug interactions, simplified:

• Warfarin: keep vitamin K intake steady (leafy greens are okay-just be consistent). Many antibiotics and herbal products (like St John’s wort) can change INR. Always check before adding anything new.
• DOACs: fewer food issues, but some medicines (certain antifungals, antivirals, anticonvulsants) can interact. Your pharmacist can run an interaction check in minutes.
• Alcohol: moderation. Heavy drinking increases bleeding risk and destabilises warfarin.

How long is “long-term”? A rule of thumb clinicians use: if the clot had a clear, temporary cause that’s gone (like surgery) and bleeding risk is moderate, 3 months is enough. If there was no clear cause or you have ongoing risk (cancer, recurrent clots), extended therapy is considered, with a regular check-in to reassess bleeding risk and preferences.

Australian context (2025): hospitals follow the VTE Clinical Care Standard from the Australian Commission on Safety and Quality in Health Care. Thrombosis and Haemostasis Society of Australia and New Zealand provides prescribing guidance. Internationally, CHEST guidelines inform duration and drug choice. You don’t need to memorise the acronyms-just use them to frame one crucial question at appointments: “How are we balancing clot risk and bleed risk for me?”

Checklists, FAQs, and next steps

Emergency signs-act now:

• Sudden shortness of breath, chest pain worse with a deep breath, fainting, or coughing up blood.
• One leg suddenly much bigger, painful, hot, and red-especially with tenderness along the calf or inner thigh.

Prevention checklist (print on your fridge):

• Move: 3 minutes every hour while awake.
• Hydrate: set a water reminder mid-morning and mid-afternoon.
• Medications: tick off doses on a weekly chart; set phone alarms.
• Compression: use stockings or sleeves if prescribed; put them on before swelling builds.
• Travel: aisle seat, stretch every hour, limit alcohol, consider stockings, ask about preventive dosing if high risk.
• After hospital: know your prevention plan, dose, and stop date; book the follow-up.

Medication safety checklist:

• Carry an updated medication list and an anticoagulant alert card.
• Before any new prescription or supplement, ask: “Does this interact with my blood thinner?”
• Have a plan for missed doses and minor bleeding (e.g., nosebleeds). If bleeding is heavy or you feel faint, seek urgent care.
• Store meds in one spot; use a pill organiser. A family member can double-check the organiser weekly-my son Landon loves ticking boxes; it’s oddly satisfying.

Mini-FAQ:

• Can walking “break a clot loose”? Gentle walking does not increase the risk of a clot travelling and is encouraged once treatment starts, unless your clinician says otherwise.
• Do compression stockings prevent clots? They help blood flow and can ease symptoms on long trips or after DVT. They are not a substitute for anticoagulants when those are indicated.
• How long until I feel normal after PE? Breathlessness often improves over weeks. If you’re not improving by 6-8 weeks or you’re getting worse, call your clinician.
• Is aspirin enough? Not for treating DVT/PE. Aspirin has a small role in very specific prevention cases but is not a treatment substitute.
• What if I keep forgetting doses? Use smartphone alarms, a pill organiser, or link dosing to daily habits (e.g., after brushing teeth). If adherence is a big issue, ask if a once-daily option suits you.
• I have kidney disease. Can I take DOACs? Often yes, with dose adjustments, but severe impairment limits options. Your doctor will check your eGFR to guide the choice.
• Do I need routine blood tests on DOACs? No routine INR checks. You still need periodic kidney and liver tests and a review of bleeding risk.

Scenarios and what to do:

• Living alone and worried you’ll miss warning signs: put a daily leg check on your calendar. Agree with a friend to text “OK” after your afternoon walk. No text? They call.
• Carer for a parent with memory issues: keep a simple dosing chart on the fridge and a locked pill dispenser. Ask the GP about blister packs from the pharmacy.
• After hip/knee replacement: expect 2-6 weeks of prevention; know the exact stop date and seek help promptly for calf swelling or chest symptoms. Don’t wait it out.
• Long-haul flight from Australia to Europe or the U.S.: plan aisle walks every hour, calf raises in your seat every 20-30 minutes, and hydration. If you had major surgery in the last 3 months, talk to your doctor about extra prevention.
• History of stomach bleeding: tell your clinician. They may choose a drug with lower GI bleeding risk and consider a stomach-protecting medicine.

Credible sources behind the advice: CDC data on hospital-associated clots; WHO statements placing VTE among top cardiovascular causes; the Australian Commission on Safety and Quality in Health Care’s VTE Clinical Care Standard; CHEST and THANZ guidance on choosing and dosing anticoagulants. These are the frameworks your clinicians trust in 2025.

A quick note from home. When Doris and I plan a long drive up the coast with the kids, we bake in stops every hour. It’s not just for Max to stretch-those five-minute walks are tiny investments in vascular health. Multiply that by a lifetime and you’ve just lowered your risk in a way no pill can replace.

Next steps you can take today:

1. Set an hourly move reminder on your phone or smartwatch.
2. Make a one-page medication list and keep it in your wallet.
3. Book a GP review if you’ve had new leg swelling, chest symptoms, or are starting/stopping any major medicines.
4. If you’re heading into hospital or surgery, ask for your VTE prevention plan in writing.
5. For carers: delegate one check-in task to another family member. Shared vigilance works better than solo effort.

If you only remember three things: move every hour, hydrate, and ask for a prevention plan any time you enter or leave hospital. Those habits cut risk more than most people think.