Medical Properties Trust (MPW -0.33%) is a high-yielding dividend stock that might look safe right now. At 13%, it offers investors a mouthwatering payout, in large part because its share price has tumbled more than 50% during the past 12 months.

The healthcare-focused real estate investment trust (REIT) has funds from operations that are strong enough right now to support its dividend, suggesting this could make for a good contrarian buy. But investors shouldn't feel too comfortable with the dividend and the stock as a whole. And assuming everything is fine could prove to be a costly mistake.

Dividend cuts don't always come with warnings

The big danger for Medical Properties investors is the possibility that the REIT's performance will get worse, perhaps there will be more tenant defaults, and then there will be a dividend cut. But the reality is that management could very well reduce the payouts before all those things happen. It will, after all, see the problems ahead before investors see them reported in the financial statements.

I've been in that situation before, when a dividend stock had a high yield of 10%, and its financials were strong enough to support the payout. But even before conditions deteriorated, management preemptively slashed the payout. And since it was a REIT that investors relied on primarily for the dividend, the stock proceeded to crash as well.

I had no prior warning, and the only saving grace for me was that I had been holding the stock long enough that after years of high dividend payouts, I didn't end up losing money on my investment, but I very well could have.

My concern is that Medical Properties could end up on a similar path.

The REIT is OK for now -- but don't assume the dividend is safe

I see the same danger ahead for Medical Properties Trust investors. Things appear to be OK right now -- the REIT's funds from operations (FFO) per share in its most recent quarter (ended March 31) was $0.31 and were higher than its $0.29 quarterly dividend payment. But that isn't a huge buffer for the company, especially if things get worse, because Medical Properties has already been dealing with uncollected rent.

There have been positive developments with hospitals reporting stronger financials that could help make Medical Properties a safer dividend stock to own; many of the REIT's tenants are hospitals. But the reality is that there's still plenty of risk in the REIT's financials, and that puts its payouts in jeopardy. One of its top tenants, Prospect Medical, didn't pay its full rent in January and February, and that could end up being the canary in the coal mine for investors.

Investors shouldn't take a chance on this dividend stock

Medical Properties Trust might maintain its dividend payments and it might be able to weather the storm that it finds itself in. But the storm could drag on for a while. A recession still hasn't hit the economy and if it does, that could put the REIT and its tenants through yet another, more serious test. That doesn't bode well for a REIT that already has a slim buffer between its FFO per share and its quarterly dividend.

Although Medical Properties's dividend is attractive, that's only if it is sustainable -- which I'm not convinced that it is right now. There's simply too much risk here for this to be a tenable investment at a time when many companies are slashing their dividends and with an uncertain future for the economy. Plus, the REIT doesn't have a good track record as an investment for success, and there's little reason to be optimistic.