AGE: Fatal Error

I got this error, what i need to change there
AGE: Fatal error: Call to a member function format() on boolean in /home/*******/wp-content/themes/blackfyre/buddypress/members/single/profile.php on line 79

In line 79 is this code:
$age = $age->format(‘Y-m-d’);
$age = floor((time() – strtotime($age)) / 31556926);
echo $age;